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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 _get_block(self):
 """Just read a single block from your current location in _fh"""

    b = self._fh.read(4) # get block size bytes
    #print self._fh.tell()
    if not b: raise StopIteration
    block_size = struct.unpack('<i',b)[0]
    return self._fh.read(block_size)