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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 delete(self, lookup):
 		""" 		If exactly one quote matches, delete it. Otherwise, 		raise a ValueError. 		"""

		lookup, num = self.split_num(lookup)
		if num:
			result = self.find_matches(lookup)[num - 1]
		else:
			result, = self.find_matches(lookup)
		self.db.delete_one(result)