def format_vars_source(): return inspect.getsource(format_vars)

gistfile1.py

>>> import pyabr.common.string

>>> pyabr.common.string.format_vars('{__name__}')
'pyabr.common.string'

>>> print pyabr.common.string.format_vars_source()
def format_vars(s, vars=None):

    if not vars:
        vars = globals()

    return s.format(**vars)

>>> exec(pyabr.common.string.format_vars_source())

>>> format_vars("{__name__}")
'__main__'