New to Python, how do I import?

I have a Python module which I have called "helpers.py".

import clr
clr.AddReference('System.Windows.Forms')
import System.Windows.Forms as SWF

def hello_world(name):
    return "Hello %s!" % (name)

def main(cmd):
    SWF.MessageBox.Show(hello_world("Fred"))
    return

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Nice and simple and I can call it and it works.

Now I have another Python module I have called "_test.py"

import helpers
import clr
clr.AddReference('System.Windows.Forms')
import System.Windows.Forms as SWF

def main(cmd):
    SWF.MessageBox.Show(hello_world("Ethel"))
    return

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Obviously I'm doing the import wrong because I get an error saying "No module named helpers". Both .py files are in the same directory. How do I correct my mistake?