{"id":183143,"date":"2024-03-18T02:18:00","date_gmt":"2024-03-18T01:18:00","guid":{"rendered":"https:\/\/datascientest.com\/en\/?p=183143"},"modified":"2024-03-14T14:29:48","modified_gmt":"2024-03-14T13:29:48","slug":"typing-and-annotation-in-python-how-does-it-work","status":"publish","type":"post","link":"https:\/\/datascientest.com\/en\/typing-and-annotation-in-python-how-does-it-work","title":{"rendered":"Typing and Annotation in Python: How does it work?"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"183143\" class=\"elementor elementor-183143\" data-elementor-post-type=\"post\">\n\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-fcc525b e-flex e-con-boxed e-con\" data-id=\"fcc525b\" data-element_type=\"container\" data-settings=\"{&quot;content_width&quot;:&quot;boxed&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-5d1f180 elementor-widget elementor-widget-heading\" data-id=\"5d1f180\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.15.0 - 02-08-2023 *\/\n.elementor-heading-title{padding:0;margin:0;line-height:1}.elementor-widget-heading .elementor-heading-title[class*=elementor-size-]>a{color:inherit;font-size:inherit;line-height:inherit}.elementor-widget-heading .elementor-heading-title.elementor-size-small{font-size:15px}.elementor-widget-heading .elementor-heading-title.elementor-size-medium{font-size:19px}.elementor-widget-heading .elementor-heading-title.elementor-size-large{font-size:29px}.elementor-widget-heading .elementor-heading-title.elementor-size-xl{font-size:39px}.elementor-widget-heading .elementor-heading-title.elementor-size-xxl{font-size:59px}<\/style><h2 class=\"elementor-heading-title elementor-size-default\">When you're learning to code in Python, the question of typing is one that is rarely considered, whereas it's unavoidable with a language like Java. So where does this \"oversight\" on the part of one of the most widely used programming languages of the last decade come from?<\/h2>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0679337 elementor-widget elementor-widget-text-editor\" data-id=\"0679337\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.15.0 - 02-08-2023 *\/\n.elementor-widget-text-editor.elementor-drop-cap-view-stacked .elementor-drop-cap{background-color:#69727d;color:#fff}.elementor-widget-text-editor.elementor-drop-cap-view-framed .elementor-drop-cap{color:#69727d;border:3px solid;background-color:transparent}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap{margin-top:8px}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap-letter{width:1em;height:1em}.elementor-widget-text-editor .elementor-drop-cap{float:left;text-align:center;line-height:1;font-size:50px}.elementor-widget-text-editor .elementor-drop-cap-letter{display:inline-block}<\/style>\t\t\t\t<p>To answer this question, it&#8217;s important to delve into a few basic concepts. <a href=\"https:\/\/datascientest.com\/en\/blue-green-devops-a-vital-approach-for-software-development\">Software development<\/a> requires a clear understanding of data typing and how data is used in different contexts. <strong>Typing in programming<\/strong> defines the nature of the values that can be taken by the data we manipulate. To test the type of a variable in Python, we use the <strong>type() function,<\/strong> which, unsurprisingly, returns the type of the object entered as the function&#8217;s parameter.<\/p><p>The function is used as follows:<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-be76a7c elementor-widget elementor-widget-shortcode\" data-id=\"be76a7c\" data-element_type=\"widget\" data-widget_type=\"shortcode.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-shortcode\"><script src=\"https:\/\/gist.github.com\/benech17\/b8ffd955b2146435b2382c8bac66d5d5.js\"><\/script><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4eca1de elementor-widget elementor-widget-text-editor\" data-id=\"4eca1de\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<span style=\"font-weight: 400;\">The type of argument is displayed using the <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">print()<\/span><\/span> function in the form:<\/span>\n<p style=\"padding-left: 40px;\"><span style=\"color: #800080;\">&gt;&gt; &lt;<\/span><span style=\"color: #339966;\">class<\/span> <span style=\"font-weight: 400; color: #ff0000;\">&#8216;int&#8217;<\/span><span style=\"color: #800080;\">&gt;<\/span><\/p>\n<span style=\"font-weight: 400;\">In the example above, we&#8217;re testing an integer numeric variable, the corresponding type is <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">int<\/span><\/span>. In Python, there are a multitude of so-called native types, you can find the exhaustive list on the <a href=\"https:\/\/docs.python.org\/fr\/3\/library\/stdtypes.html\">official documentation<\/a>.<\/span> website.\n\n<span style=\"font-weight: 400;\">Python, being <\/span><b>a dynamically typed language<\/b><span style=\"font-weight: 400;\">, is quite flexible when it comes to managing data types, but this flexibility can sometimes lead to confusion and errors. That&#8217;s where type annotations come in, adding an extra layer of clarity and type checking to Python code.<\/span>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6ac86f3 elementor-align-center button-principale elementor-widget elementor-widget-button\" data-id=\"6ac86f3\" data-element_type=\"widget\" data-widget_type=\"button.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-button-wrapper\">\n\t\t\t<a class=\"elementor-button elementor-button-link elementor-size-sm elementor-animation-grow\" href=\"\/formation-data-analyst\">\n\t\t\t\t\t\t<span class=\"elementor-button-content-wrapper\">\n\t\t\t\t\t\t<span class=\"elementor-button-text\">En savoir plus sur Python<\/span>\n\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-886fc1b e-flex e-con-boxed e-con\" data-id=\"886fc1b\" data-element_type=\"container\" data-settings=\"{&quot;content_width&quot;:&quot;boxed&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-df311ca elementor-widget elementor-widget-heading\" data-id=\"df311ca\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Typing in programming<\/h3>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3726cf1 elementor-widget elementor-widget-text-editor\" data-id=\"3726cf1\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>There are two main types of<strong> typing in programming: static typing and dynamic typing.<\/strong><\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dda32e6 elementor-widget elementor-widget-heading\" data-id=\"dda32e6\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h4 class=\"elementor-heading-title elementor-size-medium\">1. Static typing<\/h4>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f237e83 elementor-widget elementor-widget-text-editor\" data-id=\"f237e83\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">In a statically typed language, each variable must be assigned to a type specified by the programmer. Languages such as Java, C and<a href=\"https:\/\/datascientest.com\/en\/c-what-is-this-computer-language-for\"> C++<\/a> take this approach. <\/span><span style=\"font-weight: 400;\">Let&#8217;s take the example of Java for the definition of a numeric variable, the syntax is as follows:<\/span>.<\/p><p><span style=\"font-weight: 400;\"> int a <\/span><span style=\"color: #800080;\"><b>=<\/b><\/span> <span style=\"color: #339966;\"><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">;<\/span><\/span>.<\/p><p><span style=\"font-weight: 400;\"> float b <\/span><span style=\"color: #800080;\"><b>=<\/b><\/span> <span style=\"color: #339966;\"><span style=\"font-weight: 400;\">3.<\/span><span style=\"font-weight: 400;\">;<\/span><\/span><\/p><p><span style=\"font-weight: 400;\">String c <\/span><span style=\"color: #800080;\"><b>=<\/b> <span style=\"color: #ff0000;\"><span style=\"font-weight: 400;\">&#8216;Hello World&#8217;<\/span><span style=\"font-weight: 400;\">;<\/span><\/span><\/span>.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14fdf27 elementor-widget elementor-widget-text-editor\" data-id=\"14fdf27\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>You don&#8217;t<strong> need a mastery of Java<\/strong> to understand this syntax. Each variable a, b or c is introduced by its type, followed by the assigned value.<\/p><p>The static aspect of typing is clearly apparent, and to verify this, simply see what would happen if you tried to assign a new value to one of the variables. You can try it yourself on this online compiler.<\/p><p>An important advantage of this approach is the rigor it imposes on variable definition: there&#8217;s no doubt about the nature of variables, and it becomes easier for the compiler to spot type-related errors. What&#8217;s more, type checking is generally performed at compile time, which means faster execution.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5001016 elementor-widget elementor-widget-heading\" data-id=\"5001016\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h4 class=\"elementor-heading-title elementor-size-medium\">2. Dynamic typing<\/h4>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0736e68 elementor-widget elementor-widget-text-editor\" data-id=\"0736e68\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>In contrast,<strong> Python opts for dynamic typing.<\/strong> This means that typing is performed and checked after code execution, not before. So, when you define a variable in Python, you don&#8217;t have to specify its type; it&#8217;s deduced by the interpreter. What&#8217;s more, once a variable has been defined, you can assign it a new value, whatever its type, without causing an error.<\/p><p>Example:<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dc34131 elementor-widget elementor-widget-shortcode\" data-id=\"dc34131\" data-element_type=\"widget\" data-widget_type=\"shortcode.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-shortcode\"><script src=\"https:\/\/gist.github.com\/benech17\/07d82712ac5b1dc1ab1db708467ecb8d.js\"><\/script><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4b983b2 elementor-widget elementor-widget-text-editor\" data-id=\"4b983b2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>In conclusion, which typing should you choose? There&#8217;s no fixed answer to this question: it&#8217;s defined by the programming framework. If the mission demands absolute rigor and transparency in the code, then static typing is the way to go. If the programmer wants to have a free hand over the code, then the flexibility and writing speed of dynamic typing may be the right solution.<\/p><p>But if you want static typing, should you avoid Python?<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9088e40 elementor-widget elementor-widget-image\" data-id=\"9088e40\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.15.0 - 02-08-2023 *\/\n.elementor-widget-image{text-align:center}.elementor-widget-image a{display:inline-block}.elementor-widget-image a img[src$=\".svg\"]{width:48px}.elementor-widget-image img{vertical-align:middle;display:inline-block}<\/style>\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/datascientest.com\/wp-content\/uploads\/2023\/11\/typing-python.png\" title=\"\" alt=\"\" loading=\"lazy\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\"><\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c7346a3 elementor-align-center button-principale elementor-widget elementor-widget-button\" data-id=\"c7346a3\" data-element_type=\"widget\" data-widget_type=\"button.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-button-wrapper\">\n\t\t\t<a class=\"elementor-button elementor-button-link elementor-size-sm elementor-animation-grow\" href=\"https:\/\/datascientest.com\/en\/data-analyst-course\">\n\t\t\t\t\t\t<span class=\"elementor-button-content-wrapper\">\n\t\t\t\t\t\t<span class=\"elementor-button-text\">Training in Python for Data<\/span>\n\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-f5f4200 e-flex e-con-boxed e-con\" data-id=\"f5f4200\" data-element_type=\"container\" data-settings=\"{&quot;content_width&quot;:&quot;boxed&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-91ba463 elementor-widget elementor-widget-heading\" data-id=\"91ba463\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Type annotations in Python<\/h3>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-155189c elementor-widget elementor-widget-text-editor\" data-id=\"155189c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>To<strong> simulate static typing, Python offers a system of type annotations.<\/strong> Type annotations allow the programmer to specify the type of a function&#8217;s arguments and the type of its return value. For example :<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-66762fc elementor-widget elementor-widget-shortcode\" data-id=\"66762fc\" data-element_type=\"widget\" data-widget_type=\"shortcode.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-shortcode\"><script src=\"https:\/\/gist.github.com\/benech17\/afb701259ba00795e8969ddc681d24f2.js\"><\/script><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b359167 elementor-widget elementor-widget-text-editor\" data-id=\"b359167\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<span style=\"font-weight: 400;\">This function, which takes as argument a string <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">a<\/span><\/span>, worth by default <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">&#8216;Hello World&#8217;<\/span><\/span> and which displays this string as output, allows us to specify two annotations: <\/span>\n<ul>\n \t<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The first annotation corresponds to the type of variable desired as argument, <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">a: str<\/span><\/span>. Here, we <\/span><b>indicate<\/b><span style=\"font-weight: 400;\"> that the argument <\/span><span style=\"font-weight: 400;\">a<\/span><span style=\"font-weight: 400;\"> entered by the user of our function must be of type <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">str<\/span><\/span>.<\/span><\/li>\n<\/ul>\n<ul>\n \t<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The second annotation indicates the type of the output value of our function, <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">-&gt; None<\/span><\/span>. Here, we <b>indicate<\/b> that the function returns nothing, which is consistent with its purpose of <i>displaying<\/i> only a result.<\/span><\/li>\n<\/ul>\n<span style=\"font-weight: 400;\">These annotations are accessed using the <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">__annotations__<\/span><\/span> attribute, in the case of our example, we&#8217;ll have the following annotations: <\/span>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f451ecf elementor-widget elementor-widget-shortcode\" data-id=\"f451ecf\" data-element_type=\"widget\" data-widget_type=\"shortcode.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-shortcode\"><script src=\"https:\/\/gist.github.com\/benech17\/39e5b978b1299faede13440919117afe.js\"><\/script><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0177a88 elementor-widget elementor-widget-text-editor\" data-id=\"0177a88\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>It&#8217;s important to note that <a href=\"https:\/\/datascientest.com\/en\/the-power-of-python-annotations-a-guide-to-why-and-how-you-should-use-them\">these annotations are indications, not strict constraints<\/a>. Python does not prevent code execution if the actual types do not match the annotated types. However, these annotations can be very useful for understanding the programmer&#8217;s intention and detecting potential typing errors.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-34a81dd e-flex e-con-boxed e-con\" data-id=\"34a81dd\" data-element_type=\"container\" data-settings=\"{&quot;content_width&quot;:&quot;boxed&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-3201c0b elementor-widget elementor-widget-heading\" data-id=\"3201c0b\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">MyPy: a type checker for Python<\/h3>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a9c5751 elementor-widget elementor-widget-text-editor\" data-id=\"a9c5751\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">While<strong> type annotations<\/strong> are useful, they don&#8217;t provide any real type checking in Python. To fill this gap, you can use third-party tools like MyPy.<\/span><\/p><p><span style=\"font-weight: 400;\"><strong>MyPy is a Python library that checks the static typing of Python code<\/strong> and helps find bugs before your program runs. It works in conjunction with type annotations to ensure that they are respected. MyPy does not render code invalid if typing is not respected, but it does provide a detailed report of typing errors encountered. This allows the developer to correct these errors before they cause problems in code execution.<\/span><\/p><p><span style=\"font-weight: 400;\">The most common way to use it is as a debugger according to the following scheme:<\/span><\/p><ol><li style=\"list-style-type: none;\"><ol><li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Write your Python code and save it as a <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">.py<\/span><\/span>.<\/span><\/li><\/ol><\/li><\/ol><p>file.<\/p><ol><li><span style=\"font-weight: 400;\">On a terminal, enter the following command: <span style=\"background: #f5f5f5;\"><span style=\"font-weight: 400; color: #339966;\">mypy my_file.py<\/span><\/span><\/span><\/li><\/ol>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-72f48dd elementor-widget elementor-widget-text-editor\" data-id=\"72f48dd\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>If errors are detected, they will be returned by MyPy, specifying the type of error, its position in the code and the cause of the error.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-7cd648c e-flex e-con-boxed e-con\" data-id=\"7cd648c\" data-element_type=\"container\" data-settings=\"{&quot;content_width&quot;:&quot;boxed&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-ee602d9 elementor-widget elementor-widget-text-editor\" data-id=\"ee602d9\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>In conclusion,<strong> although Python is a dynamically typed language<\/strong>, the use of type annotations and type checkers like <strong>MyPy<\/strong> can greatly improve the clarity and robustness of<strong> Python code.<\/strong> These tools can be particularly useful in large software development projects, where a clear understanding of<strong> data typing is essential to maintaining high-quality code.<\/strong><\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5666561 elementor-widget elementor-widget-image\" data-id=\"5666561\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/datascientest.com\/wp-content\/uploads\/2023\/11\/typing_python.jpg\" title=\"\" alt=\"\" loading=\"lazy\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\"><\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14108b5 elementor-align-center button-principale elementor-widget elementor-widget-button\" data-id=\"14108b5\" data-element_type=\"widget\" data-widget_type=\"button.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-button-wrapper\">\n\t\t\t<a class=\"elementor-button elementor-button-link elementor-size-sm elementor-animation-grow\" href=\"https:\/\/datascientest.com\/en\/data-courses\">\n\t\t\t\t\t\t<span class=\"elementor-button-content-wrapper\">\n\t\t\t\t\t\t<span class=\"elementor-button-text\">Discover our Data training courses<\/span>\n\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0ae5809 elementor-widget elementor-widget-html\" data-id=\"0ae5809\" data-element_type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<script type=\"application\/ld+json\">\r\n{\r\n  \"@context\": \"https:\/\/schema.org\",\r\n  \"@type\": \"FAQPage\",\r\n  \"mainEntity\": [{\r\n    \"@type\": \"Question\",\r\n    \"name\": \"Qu\u2019est-ce que le Typage et l'Annotation en Python ?\",\r\n    \"acceptedAnswer\": {\r\n      \"@type\": \"Answer\",\r\n      \"text\": \"Lorsque l'on apprend \u00e0 coder en Python, la question du typage est une question que l'on ne consid\u00e8re que tr\u00e8s rarement alors que celle-ci est incontournable avec un langage comme Java. 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