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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 binaryRecordsStream(self, directory, recordLength=None, process_all=False):
 """Monitor a directory and process all binary files. File names starting with ``.`` are ignored. :param string directory: a path :param recordLength: None, int or struct format string :param bool process_all: whether to process pre-existing files :rtype: DStream .. warning:: Only ``int`` ``recordLength`` are supported in PySpark API. The ``process_all`` parameter does not exist in the PySpark API. """

        deserializer = FileBinaryStreamDeserializer(self._context,
                                                    recordLength)
        file_stream = FileStream(directory, process_all)
        self._on_stop_cb.append(file_stream.stop)
        return DStream(file_stream, self, deserializer)