How long can an identifier be in Flask Python?

In Flask Python, an identifier can be of any length. Also, there are certain rules that the users must follow to name an identifier

• It should begin with a character or an underscore or from A-Z or a-z.
• The rest of the name of identifier can contain anything from the following: A-Z or a-z or 0-9 or _.

Flask Python is case-sensitive so it will treat upper case and lower case letters differently.

There are certain words, which are reserved in Python called keywords and they cannot be used as identifiers.Some of them are listed below:

and, def, false, import, not, true, as, del, finally, in, or, try, assert, elseif, for, is, pass, while, break, else, from, lambda, print, with, class, except, global, none, raise, yield, continue, exec, if, nonlocal, return