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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, n):
 """ Consume `n` characters from the stream. """

    while len(self.buf) < n:
      chunk = self.f.recv(4096)
      if not chunk:
        raise EndOfStreamError()
      self.buf += chunk
    res, self.buf = self.buf[:n], self.buf[n:]
    return res