what are identifier in python?
In python,An identifier is a user-defined name given to identities like class, functions, variables, modules, or any other object in Python.
Rules for writing Identifiers in Python

Here is the simplified list of Python identifier rules:
• Allowed Characters: Use only letters (A-Z, a-z), digits (0-9), and underscores (_).
• First Character: Must start with a letter or an underscore. It cannot start with a digit.
• No Keywords: Do not use reserved words like if, for, or class.
• No Special Symbols: Do not use spaces or symbols like @, #, $, or -.
• Case-Sensitive: Capitalisation matters. User and user are different names.
• Length: There is no limit on how long the name can be.

Python Valid Identifiers Example

  • abc123
  • abc_de
  • _abc
  • ABC
  • abc

Python Invalid Identifiers Example

  • 123abc
  • abc@
  • 123
  • for