gistfile1.py

from macropy.macros.string_interp import macros, s

a, b = 1, 2

c = s%"%{a} apple and %{b} bananas"

gistfile2.pytb

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unsupported operand type(s) for %: 'NoneType' and 'str'

You can't use macros in a single file. You need to import macropy before you import your code which uses macro substitution. So in this example, you would need a main.py which looks like

import macropy.core.macros
import gistfile1

You can look at run.py to see how we run our unittests.