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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 _frombuffer(ptr, frames, channels, dtype):
 """Create NumPy array from a pointer to some memory."""

    framesize = channels * dtype.itemsize
    data = np.frombuffer(ffi.buffer(ptr, frames * framesize), dtype=dtype)
    data.shape = -1, channels
    return data