How to keep submodule names out of the name space of a Python package?

Question

I want the interface of some module to contain a certain number of functions and classes (and nothing else). I could implement all of those in a single file, and would easily get the interface I want. But since there is a lot of code, I'd prefer to split the whole thing up into several files, say

mypackage/
    __init__.py
    a.py
    b.py
    c.py
    d.py

To get the desired interface anyway, I define an __init__.py file for the package that imports all public symbols from a, b, c and d:

from a import func_a1, func_a2, ClassA1, ClassA2
from b import func_b1, func_b2, ClassB1, ClassB2
from c import func_c1, func_c2, ClassC1, ClassC2
from d import func_d1, func_d2, ClassD1, ClassD2

If I import the package using

import mypackage

the package namespace also contains the symbols a, b, c and d. These names are implementation details and not part of my interface. I don't want them to appear as "public" symbols. What is the best way of getting rid of them?

The options I considered are

1. Use a single module instead of a package. The interface will look fine, but the implementation will get less clear than it is now.

2. Add the line

   del a, b, c, d
   

   to the end of __init__.py. Works ok, but seems like a hack. (For example, you can't import __init__ any more, which works without this line.)

3. Rename a, b, c and d to _a, _b, _c and _d. Now they are included in mypackage's namespace as "private" symbols, which I'm fine with, but it feels a bit strange that all my filenames start with an underscore (in reality, there are of course more than four submodules).

Any better suggestions? Or thoughts on which option to prefer?

Or am I just to anal and shouldn't care about the whole thing?

Answer 1

If you really want to remove the names from the namespace then you can just use the del statement on them and they'll disappear like the wind.