What are modules really for?

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    Nick> One thing I find weird about python is the idea of a module. Why
    Nick> is this needed when there are already the ideas of class, file,
    Nick> and package?

A module is a namespace object that maps one-to-one to a file (ignoring the
new module's features).  A file by itself is just a collection of bytes and
has no features to interpret the structure of its contents as a namespace.

    Nick> Python seems to let you group classes together in one file and
    Nick> call it a module, but what for?

You can define many other types of objects in modules besides classes.

    Nick> With Python an inherited method could be in one of many base
    Nick> classes and/or mixins and there seems no particular logic as to
    Nick> what the filename would be.

I agree mixins can be troublesome.  That's a problem peculiar to multiple
inheritance, not strictly to Python.  I'm sure you can create file/class
relationships in Java or C++ that make it challenging to find the definition
of a mixin.  I don't view multiple inheritance as a gotta-have feature of
OOP and avoid it when I can.  Smalltalk has lived happily without multiple
inheritance for a few decades now.

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