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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 normalize(self, **kwargs):
 		""" 		Adjust the offsetvector so that a particular instrument has 		the desired offset. All other instruments have their 		offsets adjusted so that the relative offsets are 		preserved. The instrument to noramlize, and the offset one 		wishes it to have, are provided as a key-word argument. 		The return value is the time slide dictionary, which is 		modified in place. 		If more than one key-word argument is provided the keys are 		sorted and considered in order until a key is found that is 		in the offset vector. The offset vector is normalized to 		that value. This function is a no-op if no key-word 		argument is found that applies. 		Example: 		offsetvector({'H2': 0, 'H1': 0, 'L1': 0}) 		offsetvector({'H2': 5, 'H1': 5}) 		"""

		# FIXME:  should it be performed in place?  if it should
		# be, the should there be no return value?
		for key, offset in sorted(kwargs.items()):
			if key in self:
				delta = offset - self[key]
				for key in self.keys():
					self[key] += delta
				break
		return self