Python Identifiers

A Python identifier is
a name used to identify a variable, function, class, module or other object.

An identifier starts
with a letter A to Z or a to z or an underscore (_) followed by zero or more
letters, underscores and digits (0 to 9).

Python does not allow
punctuation characters such as @, $, and % within identifiers.

Python is a case
sensitive programming language. Thus, Man and man are
two different identifiers in Python.

Naming conventions for
Python identifiers −

• Class names start with an uppercase
  letter. All other identifiers start with a lowercase letter.


• Starting an identifier with a
  single leading underscore indicates that the identifier is private.


• Starting an identifier with two
  leading underscores indicates a strongly private identifier.


• If the identifier also ends with
  two trailing underscores, the identifier is a language-defined special
  name.