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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 dock(self, other):
		'''
			The opposite of concatenation. Remove a common suffix from the present
			pattern; that is, from each of its constituent concs.
			AYZ|BYZ|CYZ - YZ = A|B|C.
		'''
		return pattern(*[c.dock(other) for c in self.concs])