python identifier naming rules :
The first character of an identifier must be a letter in the alphabet (uppercase or lowercase) or an underscore (' _ ').
Other parts of the identifier name can consist of a letter (uppercase or lowercase), an underscore (' _ '), or a number (0-9).
The identifier name is case-sensitive. For example, MyName and myname are not an identifier. Note that the former lowercase n and
The latter in uppercase N.
Examples of valid identifier names are I, __my_name, name_23, and A1B2_C3.
Examples of invalid identifier names are 2things, this was spaced out, and my-name.
C language identifier naming rules:
Identifiers can only be made up of uppercase and lowercase letters, underscores (_), and Arabic numerals. The first character of an identifier must be an uppercase or lowercase letter or an underscore, not a number
Case sensitive
Summary: The same as the naming rules/sweat ....