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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def common(self, other):
		'''
			Find the shared part of two multipliers. This is the largest multiplier
			which can be safely subtracted from both the originals. This may
			return the "zero" multiplier.
		'''
		mandatory = min(self.mandatory, other.mandatory)
		optional = min(self.optional, other.optional)
		return multiplier(mandatory, mandatory + optional)