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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 GetBaseFiles(self, diff):
 		"""Helper that calls GetBase file for each file in the patch. 		Returns: 			A dictionary that maps from filename to GetBaseFile's tuple. Filenames 			are retrieved based on lines that start with "Index:" or 			"Property changes on:". 		"""

		files = {}
		for line in diff.splitlines(True):
			if line.startswith('Index:') or line.startswith('Property changes on:'):
				unused, filename = line.split(':', 1)
				# On Windows if a file has property changes its filename uses '\'
				# instead of '/'.
				filename = to_slash(filename.strip())
				files[filename] = self.GetBaseFile(filename)
		return files