How to compile a string of Python code into a module whose functions can be called?

Question

In Python, I have a string of some Python source code containing functions like:

mySrc = '''
def foo():
    print("foo")

def bar():
    print("bar")
'''

I'd like to compile this string into some kind of module-like object so I can call the functions contained in the code.

Here's pseudo-code for what I'd like to do:

myMod = myCompile(mySrc)
myMod.foo()

Is this possible in Python? I've tried this, but it does not work:

myMod = compile(mySrc, '', 'exec')
myMod.foo()

This produces an error message like this:

<code object <module> at 0x104154730, file "", line 1>Traceback (most recent call last):
  File "myfile.py", line XX, in run
    myMod.foo()
AttributeError: 'code' object has no attribute 'foo'

Answer 1

You have to both compile and execute it:

myMod = compile(mySrc, '', 'exec')
exec(myMod)
foo()

You can pass dicts to exec to stop foo from “leaking” out. Combine it with a module object created using types.ModuleType:

from types import ModuleType
…
compiled = compile(mySrc, '', 'exec')
module = ModuleType("testmodule")
exec(compiled, module.__dict__)