In the Python world, the sentiment is exactly the opposite. I remember reading in "Programming Python" this common idiom:

#!/usr/bin/env python
# module mymod2.py

def cube(n):
   return n ** 3

# when 'import'ed, __name__ is 'mymod2'
# when executed, __name__ is '__main__'
if __name__ == '__main__':
   if cube(15) != 3375:
      print "Error, cube(15) is not correct"
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