Question

I have three python files

one.py, two.py, three.py

one.py

from one.py I call

import two as two  
    two.three()

in two.py I have

def two():
    "catch the error here then import and call three()"
    import three as three

in three.py I have

def three():
    print "three called"

so naturally I am getting:

AttributeError: ‘function’ object has no attribute ‘three’

My question is:

Is there a way to have two.py capture the error then import three.py and then call three()?

______________edit________________V
I can call it like this:

two().three()

def two():
    import three as three
    return three

but I would like to call it like so:

two.three()

So essentially it would auto exec def two():

Answer 1

Here’s the solution I came up with. I confess that I was inspired by your question to try to figure this out, so I don’t completely understand it myself. The magic happens in two.py where the attempt to access and then call the three method of two is handled by the __getattr__ method of the method_router class. It uses __import__ to import the indicated module by name (a string), and then imitates the from blah import blah by calling getattr() again on the imported module.

one.py

from two import two
two.three()

two.py

class method_router(object):
    def __getattr__(self, name):
        mod = __import__(name)
        return getattr(mod, name)

two = method_router()

three.py

def three():
    print("three called")