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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, frames, raw=False):
 """Read samples from an input stream. The function does not return until the required number of frames has been read. This may involve waiting for the operating system to supply the data. If raw data is requested, the raw cffi data buffer is returned. Otherwise, a numpy array of the appropriate dtype with one column per channel is returned. """

        channels, _ = _split(self.channels)
        dtype, _ = _split(self.dtype)
        data = ffi.new("signed char[]", channels * dtype.itemsize * frames)
        self._handle_error(_pa.Pa_ReadStream(self._stream, data, frames))
        if not raw:
            data = np.frombuffer(ffi.buffer(data), dtype=dtype)
            data.shape = frames, channels
        return data