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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 _setComparasionOperator(self, field, oper):
 		"""Sets correct operator for given string representation"""


		if oper != '':
			validOperators = {
				'eq':'eq',
				'equals':'eq',
				'=':'eq',
				'==':'eq',
				'cn':'cn',
				'contains':'cn',
				'%%':'cn',
				'%':'cn',
				'*':'cn',
				'bw':'bw',
				'begins with':'bw',
				'^':'bw',
				'ew':'ew',
				'ends with':'ew',
				'$':'ew',
				'gt':'gt',
				'greater than':'gt',
				'>':'gt',
				'gte':'gte',
				'greater than or equals':'gte',
				'>=':'gte',
				'lt':'lt',
				'less than':'lt',
				'<':'lt',
				'lte':'lte',
				'less than or equals':'lte',
				'<=':'lte',
				'neq':'neq',
				'not equals':'neq',
				'!=':'neq',
				'<>':'neq'
			}

		if not string.lower(oper) in validOperators.keys():
			raise FMError, 'Invalid operator "'+ oper + '" for "' + field + '"'

		oper = validOperators[oper.lower()]
		self._dbParams.append(
			["%s.op" % field, oper]
		)