{"id":27406,"date":"2018-11-20T09:26:05","date_gmt":"2018-11-20T03:56:05","guid":{"rendered":"https:\/\/data-flair.training\/blogs\/?p=27406"},"modified":"2026-04-13T12:03:23","modified_gmt":"2026-04-13T06:33:23","slug":"identifiers-in-python","status":"publish","type":"post","link":"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/","title":{"rendered":"Identifiers in Python &#8211; Naming Rules and Best Practices"},"content":{"rendered":"<div class='__iawmlf-post-loop-links' style='display:none;' data-iawmlf-post-links='[{&quot;id&quot;:1729,&quot;href&quot;:&quot;https:\\\/\\\/quizorbit.com\\\/quiz-on-python-identifiers&quot;,&quot;archived_href&quot;:&quot;http:\\\/\\\/web-wp.archive.org\\\/web\\\/20210804210853\\\/https:\\\/\\\/quizorbit.com\\\/quiz-on-python-identifiers\\\/&quot;,&quot;redirect_href&quot;:&quot;&quot;,&quot;checks&quot;:[{&quot;date&quot;:&quot;2025-12-09 21:01:33&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2025-12-13 14:20:34&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2025-12-17 06:46:05&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2025-12-23 18:39:57&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2025-12-27 15:00:52&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2025-12-31 09:46:58&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-04 13:43:03&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-10 00:26:44&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-18 23:52:27&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-24 08:41:35&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-28 13:45:11&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-01-31 14:08:14&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-04 05:54:35&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-07 07:56:51&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-11 03:41:27&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-18 12:39:31&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-22 11:28:06&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-02-25 19:15:15&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-03-08 03:48:26&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-03-11 04:11:06&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-03-14 14:12:01&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-03-31 04:54:46&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-04-03 19:26:24&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-04-09 15:29:41&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-04-13 04:56:44&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-04-21 14:17:52&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-04-24 14:46:29&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-05-04 00:50:01&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-05-07 11:07:42&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-05-11 17:28:03&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-05-23 10:59:46&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-05-27 05:26:58&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-06-03 12:56:59&quot;,&quot;http_code&quot;:403},{&quot;date&quot;:&quot;2026-06-07 20:31:38&quot;,&quot;http_code&quot;:403}],&quot;broken&quot;:true,&quot;last_checked&quot;:{&quot;date&quot;:&quot;2026-06-07 20:31:38&quot;,&quot;http_code&quot;:403},&quot;process&quot;:&quot;done&quot;}]'><\/div>\n<p><span style=\"font-weight: 400\"> Today, in this Python tutorial, we will learn about identifiers in Python and how to name them. <\/span><\/p>\n<p><span style=\"font-weight: 400\">Moreover, we will see the rules, best practices, reserved classes in Python Identifiers. Also, we will test the validity of identifiers in Python.\u00a0<\/span><\/p>\n<p>So, let&#8217;s start Identifiers in Python.<\/p>\n<h3>What are Identifiers in Python?<\/h3>\n<p><span style=\"font-weight: 400\">We can define identifiers in Python in few ways:<\/span><\/p>\n<ul>\n<li><span style=\"font-weight: 400\">An identifier is a user-defined name to represent a variable, a function, a class, a module, or any other object.<\/span><\/li>\n<li><span style=\"font-weight: 400\">It is a programmable entity in Python- one with a name.<\/span><\/li>\n<li><span style=\"font-weight: 400\">It is a name given to the fundamental building blocks in a program.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400\">Python Identifier Naming Rules<\/span><\/h3>\n<h4><span style=\"font-weight: 400\">1. Rules for naming Identifiers in Python<\/span><\/h4>\n<p><span style=\"font-weight: 400\">So we know what a Python Identifier is. But can we name it anything? Or do certain rules apply? <\/span><\/p>\n<p><span style=\"font-weight: 400\">Well, we do have five rules to follow when naming identifiers in Python:<\/span><\/p>\n<p><span style=\"font-weight: 400\">a. A Python identifier can be a combination of lowercase\/ uppercase letters, digits, or an underscore. The following characters are valid:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Lowercase letters (a to z)<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Uppercase letters (A to Z)<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Digits (0 to 9)<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Underscore (_)<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400\">Some valid names are:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">myVar<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">var_3<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">this_works_too<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400\">b. An identifier in python cannot begin with a digit. It must start with a letter or underscore.<\/span><br \/>\n<span style=\"font-weight: 400\">Some valid names:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">_9lives<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">lives9<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400\">An invalid name:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">9lives<\/span><\/li>\n<\/ul>\n<div id=\"attachment_27443\" style=\"width: 240px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/two-1.png\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-27443\" class=\"wp-image-27443 size-full\" src=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/two-1.png\" alt=\"Identifiers in Python\" width=\"230\" height=\"66\" srcset=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/two-1.png 230w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/two-1-150x43.png 150w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/><\/a><p id=\"caption-attachment-27443\" class=\"wp-caption-text\">Identifiers in Python &#8211; Naming Rules<\/p><\/div>\n<p><span style=\"font-weight: 400\">c. We cannot use spaces or special symbols in the identifier name. Some of these are:<\/span><br \/>\n<span style=\"font-weight: 400\">!<\/span><br \/>\n<span style=\"font-weight: 400\">@<\/span><br \/>\n<span style=\"font-weight: 400\">#<\/span><br \/>\n<span style=\"font-weight: 400\">$<\/span><br \/>\n<span style=\"font-weight: 400\">%<\/span><br \/>\n<span style=\"font-weight: 400\">.<\/span><\/p>\n<div id=\"attachment_27445\" style=\"width: 248px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/three-1.png\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-27445\" class=\"wp-image-27445 size-full\" src=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/three-1.png\" alt=\"Identifiers in Python\" width=\"238\" height=\"34\" srcset=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/three-1.png 238w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/three-1-150x21.png 150w\" sizes=\"auto, (max-width: 238px) 100vw, 238px\" \/><\/a><p id=\"caption-attachment-27445\" class=\"wp-caption-text\">Identifiers in Python &#8211; Naming Rules in Python<\/p><\/div>\n<p><span style=\"font-weight: 400\">d. We cannot use a keyword as an identifier. <\/span><\/p>\n<p><span style=\"font-weight: 400\">Keywords are reserved names in Python, and using one of those as a name for an identifier will result in a SyntaxError.<\/span><\/p>\n<div id=\"attachment_27446\" style=\"width: 241px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four-1.png\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-27446\" class=\"wp-image-27446 size-full\" src=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four-1.png\" alt=\"Identifiers in Python\" width=\"231\" height=\"34\" srcset=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four-1.png 231w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four-1-150x22.png 150w\" sizes=\"auto, (max-width: 231px) 100vw, 231px\" \/><\/a><p id=\"caption-attachment-27446\" class=\"wp-caption-text\">Identifiers in Python &#8211; Identifiers Naming Rules<\/p><\/div>\n<div id=\"attachment_27447\" style=\"width: 498px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four1.png\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-27447\" class=\"wp-image-27447 size-full\" src=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four1.png\" alt=\"Identifiers in Python\" width=\"488\" height=\"36\" srcset=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four1.png 488w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four1-150x11.png 150w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/09\/four1-300x22.png 300w\" sizes=\"auto, (max-width: 488px) 100vw, 488px\" \/><\/a><p id=\"caption-attachment-27447\" class=\"wp-caption-text\">Naming Rules in Python Identifiers<\/p><\/div>\n<p><span style=\"font-weight: 400\">e. An identifier in python can be as long as you want. According to the docs, you can have an identifier of infinite length. <\/span><\/p>\n<p><span style=\"font-weight: 400\">However, the PEP-8 standard sets a rule that you should limit all lines to a maximum of 79 characters.<\/span><\/p>\n<h4><span style=\"font-weight: 400\">2. Lexical Definitions in Python Identifiers<\/span><\/h4>\n<p><span style=\"font-weight: 400\">To sum those rules up lexically, we can say:<\/span><br \/>\n<b><\/b><\/p>\n<ul>\n<li><b>identifier ::= (letter | \u201c_\u201d) (letter | digit | \u201c_\u201d)*<\/b><span style=\"font-weight: 400\"> \u00a0\u00a0<\/span> <span style=\"font-weight: 400\">#It has to begin with a letter or an underscore; letters, digits, or\/and underscores may follow<\/span><br \/>\n<b><\/b><\/li>\n<li><b>letter ::= lowercase | uppercase<\/b> <span style=\"font-weight: 400\">#Anything from a-z and from A-Z<\/span><br \/>\n<b><\/b><\/li>\n<li><b>lowercase ::= \u201ca\u201d \u2026 \u201cz\u201d<\/b> <span style=\"font-weight: 400\">#Lowercase letters a to z<\/span><br \/>\n<b><\/b><\/li>\n<li><b>uppercase ::= \u201cA\u201d \u2026 \u201cZ\u201d<\/b> <span style=\"font-weight: 400\">#Uppercase letters A to Z<\/span><br \/>\n<b><\/b><\/li>\n<li><b>digit ::= \u201c0\u201d \u2026 \u201c9\u201d<\/b> <span style=\"font-weight: 400\">#Integers 0 to 9<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400\">Best Practices for Identifiers in Python<\/span><\/h3>\n<p><span style=\"font-weight: 400\">While it\u2019s mandatory to follow the rules, it is also good to follow some recommended practices:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Begin class names with an uppercase letter, begin all other identifiers with a lowercase letter<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Begin private identifiers with an underscore (_); Note that this doesn\u2019t make a variable private, but discourages the user from attempting to access it<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Put __ around names of magic methods (use leading and trailing double underscores), avoid doing this to anything else.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Use leading double underscores only when dealing with mangling.<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Prefer using names longer than one character- index=1 is better than i=1<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Use underscores to combine words in an identifier, like in this_is_an_identifier<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Since Python is <\/span><span style=\"font-weight: 400\">case-sensitive<\/span><span style=\"font-weight: 400\">, name and Name are two different identifiers.<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Use camel case for naming. Let\u2019s just clear the air here by saying camel case is myVarOne and Pascal case is MyVarOne.<\/span><\/li>\n<li>Some words are reserved by Python, like for, while, or class. You cannot use these keywords as identifiers.<\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400\">Testing the Validity of Identifiers in Python<\/span><\/h3>\n<p><span style=\"font-weight: 400\">While it is great to follow the rules and guidelines, we can test an identifier\u2019s validity just to be sure. For this, we make use of the keyword.iskeyword() function.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The <\/span><i><span style=\"font-weight: 400\">keyword<\/span><\/i><span style=\"font-weight: 400\"> module lets us determine whether a string is a keyword. It has two functions:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\"><strong>keyword.iskeyword(s)-<\/strong> If s is a Python keyword, return true<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\"><strong>Keyword.kwlist-<\/strong> Return a sequence holding all keywords the interpreter understands. This includes even those that are active only when certain __future__ statements are in effect.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400\">Coming back to iskeyword(s), it returns True if the string <\/span><i><span style=\"font-weight: 400\">s<\/span><\/i><span style=\"font-weight: 400\"> is a reserved keyword. Else, it returns False. Let\u2019s import this module.<\/span><\/p>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; import keyword\r\n&gt;&gt;&gt; keyword.iskeyword('_$$_')<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>False<\/strong><\/div>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; keyword.iskeyword('return')<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>True<\/strong><\/div>\n<p><span style=\"font-weight: 400\">Also, the str.isidentifier() function will tell us if a string is a valid identifier. This is available since Python 3.0.<\/span><\/p>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; '__$$__'.isidentifier()<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>False<\/strong><\/div>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; '__99__'.isidentifier()<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>True<\/strong><\/div>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; '9lives'.isidentifier()<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>False<\/strong><\/div>\n<pre class=\"EnlighterJSRAW\">&gt;&gt;&gt; '9.5okay'.isidentifier()<\/pre>\n<p><strong>Output<\/strong><\/p>\n<div class=\"code-output\"><strong>False<\/strong><\/div>\n<h3><span style=\"font-weight: 400\">Reserved Classes of Python Identifiers<\/span><\/h3>\n<p><span style=\"font-weight: 400\">Let us talk about classes of identifiers in Python. Some classes have special meanings, and to identify them, we use patterns of leading and trailing underscores:<\/span><\/p>\n<h4><span style=\"font-weight: 400\">1. Single Leading Underscore (_*)<\/span><\/h4>\n<p><span style=\"font-weight: 400\">We use a <\/span><span style=\"font-weight: 400\">Single Leading Underscore (_*) <\/span><span style=\"font-weight: 400\">identifier to store the result of the last evaluation in the interactive interpreter. <\/span><\/p>\n<p><span style=\"font-weight: 400\">This result is stored in the __builtin__ module. Importing a module as <\/span><i><span style=\"font-weight: 400\">from module import *<\/span><\/i><span style=\"font-weight: 400\"> does not import such private variables.<\/span><\/p>\n<p>A single underscore means that the method, variable, or function is meant for internal use only. The names that start with a single underscore are usually not imported from a module import in Python.<\/p>\n<h4><span style=\"font-weight: 400\">2. Leading and Trailing Double Underscores (__*__)<\/span><\/h4>\n<p><span style=\"font-weight: 400\">These are system-defined names (by the <strong>interpreter<\/strong>). <\/span><\/p>\n<p><span style=\"font-weight: 400\">A class can implement operations to be invoked by special syntax using methods with special names. <\/span><\/p>\n<p><span style=\"font-weight: 400\">Consider this an attempt at operator overloading in a Pythonic fashion. One such special\/ magic method is <\/span><i><span style=\"font-weight: 400\">__getitem__()<\/span><\/i><span style=\"font-weight: 400\">. Then, x[i] is equivalent to x.__getitem__(i). <\/span><\/p>\n<p><span style=\"font-weight: 400\">In the near future, the set of names of this class in Python may be extended.<\/span><\/p>\n<h4><span style=\"font-weight: 400\">3. Leading Double Underscores (__*)<\/span><\/h4>\n<p><span style=\"font-weight: 400\">These are class-private names. Within a class definition, the interpreter rewrites (mangles) such a name to avoid name clashes between the private attributes of base and derived classes.<\/span><\/p>\n<p>When you have completed the learning now, do not forget to take <a href=\"https:\/\/quizorbit.com\/quiz-on-python-identifiers\/\">Quiz on Python Identifiers<\/a> to check your knowledge. Also, attempt Interview Questions as below.<\/p>\n<h3>Python Interview Questions on Identifiers in Python<\/h3>\n<p>1. What are identifiers in Python?<\/p>\n<p>2. What is a valid identifier in Python?<\/p>\n<p>3. Explain identifiers with example.<\/p>\n<p>4. What are reserved classes of Python Identifiers?<\/p>\n<p>5. Explain some of the rules for naming identifiers in Python.<\/p>\n<h3><span style=\"font-weight: 400\">Conclusion<\/span><\/h3>\n<p><span style=\"font-weight: 400\">Hence, in this Python Identifiers, we discussed the meaning of Identifiers in Python. <\/span><\/p>\n<p><span style=\"font-weight: 400\">Moreover, we learned naming rules and best practices in Python Identifiers. Also, we discussed reserved classes in Python Identifier.\u00a0<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Today, in this Python tutorial, we will learn about identifiers in Python and how to name them. Moreover, we will see the rules, best practices, reserved classes in Python Identifiers. Also, we will test&#46;&#46;&#46;<\/p>\n","protected":false},"author":5,"featured_media":84804,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[46],"tags":[8029,10588,11570,14648,15440],"class_list":["post-27406","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-python","tag-keyword-module","tag-python-identifier-naming-rules","tag-reserved-classes-of-python-identifiers","tag-testing-the-validity-of-identifiers-in-python","tag-ways-to-define-identifiers-in-python"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Identifiers in Python - Naming Rules and Best Practices - DataFlair<\/title>\n<meta name=\"description\" content=\"Identifiers in Python - what are Python Identifiers, Reserved Classes, Testing the Validity, identifiers Naming Rules and best practices\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Identifiers in Python - Naming Rules and Best Practices - DataFlair\" \/>\n<meta property=\"og:description\" content=\"Identifiers in Python - what are Python Identifiers, Reserved Classes, Testing the Validity, identifiers Naming Rules and best practices\" \/>\n<meta property=\"og:url\" content=\"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/\" \/>\n<meta property=\"og:site_name\" content=\"DataFlair\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/DataFlairWS\/\" \/>\n<meta property=\"article:published_time\" content=\"2018-11-20T03:56:05+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-04-13T06:33:23+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/11\/Identifiers-in-Python.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"628\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"DataFlair Team\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@DataFlairWS\" \/>\n<meta name=\"twitter:site\" content=\"@DataFlairWS\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"DataFlair Team\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"6 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Identifiers in Python - Naming Rules and Best Practices - DataFlair","description":"Identifiers in Python - what are Python Identifiers, Reserved Classes, Testing the Validity, identifiers Naming Rules and best practices","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/","og_locale":"en_US","og_type":"article","og_title":"Identifiers in Python - Naming Rules and Best Practices - DataFlair","og_description":"Identifiers in Python - what are Python Identifiers, Reserved Classes, Testing the Validity, identifiers Naming Rules and best practices","og_url":"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/","og_site_name":"DataFlair","article_publisher":"https:\/\/www.facebook.com\/DataFlairWS\/","article_published_time":"2018-11-20T03:56:05+00:00","article_modified_time":"2026-04-13T06:33:23+00:00","og_image":[{"width":1200,"height":628,"url":"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2018\/11\/Identifiers-in-Python.jpg","type":"image\/jpeg"}],"author":"DataFlair Team","twitter_card":"summary_large_image","twitter_creator":"@DataFlairWS","twitter_site":"@DataFlairWS","twitter_misc":{"Written by":"DataFlair Team","Est. reading time":"6 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/#article","isPartOf":{"@id":"https:\/\/data-flair.training\/blogs\/identifiers-in-python\/"},"author":{"name":"DataFlair Team","@id":"https:\/\/data-flair.training\/blogs\/#\/schema\/person\/7f83c342f5d1632d6f7b4b0b0f447823"},"headline":"Identifiers in Python &#8211; 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