Here I present my style rules, developed over more that 40 years of programming. I was quite pleased when I learned that they mostly comply with PEP 8.
All classes are written in CamelCase, capitalizing each word and glueing them together without underscore.
All methods (functions) are witten in camelCase: starting with a lower case letter. If more words are needed they are capitalized, again no underscores.
Instance attributes are also written in camelCase. Some of them are read-only, meaning they can be enquired at a certain stage in the objects existence. It is indicated in the documentation whether an attribute is read-only.
Class attributes are written as all capitalized WORDS. They act as constants and should not be changed.
There is very little difference between private and public items as in python the difference between private and public exists only by convention.
Code statements should read like sentences optimized for the user/coder to read. The computer does not care as long as it is grammatically correct. See Obfuscated C, a competition in writing unreadable, but working code for a bad example.
Readable sentences have spaces between words. Operators are words: + reads
as "plus", = reads as "is". So operators have spaces on each side.
Except when the "=" is part of a keyword argument. In that case there are
no spaces around it. To visually connect the argument to the keyword.
Brackets as ()[]{} have spaces too if they are selfstanding. E.g. in grouping things together, in equations, tuples, lists or dictionaries.
If parentheses, (), are part of a function the opening parenthesis clings to the functionname, followed by a space. The closing one is preceeded and followed by a space.
Brackets, [], that index an array or a dictionary, have no spaces at all, indicating the close connection between the index and the indexed item.
The same close relationship exists between an object and its methods or attributes. So the connecting dot, ., has no spaces.
The comma is fuctioning as a punctuation mark, separating items in a list or a dictionary. So it has a space after it, but not before.
The colon has different tasks. It announces a new indented block of code. To make this task clear, it should stand alone with a space in front of it. The other task is to separate items in a dictionary: something between a separator and an operator.
All classes and methods have a document string in which the usage is explained. The attributes of the classes and the parameters of the methods are also listed and explained. Some minimal examples are present in the class documentation.