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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 StartFileFetch(self, pathspec, request_data=None):
 """The entry point for this flow mixin - Schedules new file transfer."""

    # Create an index so we can find this pathspec later.
    self.state.indexed_pathspecs.append(pathspec)
    self.state.request_data_list.append(request_data)
    self._TryToStartNextPathspec()