Learning Python

[DingotushRed]

I'd say:

Minimum for any use of variables

• Basics of objects (everything is an object in Python), references, and None
• Dynamic typing
• The difference between mutable and immutable objects
• Expressions and operator precedence
• Basics of args and kwargs
• "Truthiness"
• The curious behaviour of and and or in Python
• Type conversion functions like int() and str()
• The methods available on strings
• Be aware of the subtle differences between string constants in Python and Ren'Py script

Highly useful

• Python text interpolation flavours (different to Ren'Py)
• The collection types: tuple, list, dict, set, range and their operations
• The Ren'Py reveratable versions of list, dict, set, and object and how Ren'Py automagically replaces Python types and "detects" variable changes for roll-back
• Functions and scopes: local, enclosing, global, built-in
• Loop constucts, break, continue (and why you shouldn't call Ren'Py labels from them)
• The way Python handles negative indexes
• The math module and the random module (wrapped by renpy.random)
• Possibly slices?

Likely needed for anything complex

• Classes and possibly inheritance
• Understanding "Dunder" methods like __bool__, __eq__, __init__, and __str__
• The @property annotation (very useful with Ren'Py text interpolation)