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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 _GeneratePathString(self, mediator, pathspec, hashes):
 """Generates a string containing a pathspec and its hashes. Args: mediator (AnalysisMediator):
 mediates interactions between analysis plugins and other components, such as storage and dfvfs. pathspec (dfvfs.Pathspec):
 the path specification) to generate a string for. hashes (dict[str, str]):
 mapping of hash attribute names to the value of that hash for the path specification being processed. Returns: str: string of the form "display_name: hash_type=hash_value". For example, "OS:/path/spec: test_hash=4 other_hash=5". """

    display_name = mediator.GetDisplayNameForPathSpec(pathspec)
    path_string = '{0:s}:'.format(display_name)
    for hash_name, hash_value in sorted(hashes.items()):
      path_string = '{0:s} {1:s}={2:s}'.format(
          path_string, hash_name, hash_value)
    return path_string