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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 _setLogicalOperator(self, lop):
 		"""Sets the way the find fields should be combined together."""


		if not lop.lower() in ['and', 'or']:
			raise FMError, 'Unsupported logical operator (not one of "and" or "or").'

		self._lop = lop.lower()