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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 to_segmentlistdict(self):
 		""" 		Return a segmentlistdict object describing the instruments 		and times spanned by the entries in this Cache. The return 		value is coalesced. 		"""

		d = segments.segmentlistdict()
		for entry in self:
			d |= entry.segmentlistdict
		return d