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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 read(self, length, dummy=None):
 """Stub Read method."""

    assert not self.closed
    data = self.expected_read_data.pop(0)
    if length < len(data):
      raise ValueError(
          'Overflow packet length. Read %d bytes, got %d bytes: %s',
          length, len(data), self._dotify(data))
    return data