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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 GetTopLevel(self, file_object):
 """Returns the deserialized content of a plist as a dictionary object. Args: file_object (dfvfs.FileIO):
 a file-like object to parse. Returns: dict[str, object]: contents of the plist. Raises: UnableToParseFile: when the file cannot be parsed. """

    try:
      top_level_object = biplist.readPlist(file_object)

    except (biplist.InvalidPlistException,
            biplist.NotBinaryPlistException) as exception:
      raise errors.UnableToParseFile(
          'Unable to parse plist with error: {0!s}'.format(exception))

    return top_level_object