document module __init__

[stevengj]

Module initialization functions were added in #1268 and updated in #5960, but never seem to have been documented (outside of the NEWS file).

[pluskid]

When is the __init__ function of a module called? Is there any way to explicitly initialize a module?

My issue is that I need a lower level wrap of a function into BLAS. But calling my own wrapper will crash since the BLAS library has not been initialized. Currently I make a dummy call to the built-in BLAS procedures to get the library initialized. But I wander is there better way to do that?

[stevengj]

I think __init__ is called when the module is loaded into memory for the first time, e.g. via import or require or using.

[pluskid]

@stevengj Yes, that works! Thanks!