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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 integer_decimation(data, decimation_factor):
 """ Downsampling by applying a simple integer decimation. Make sure that no signal is present in frequency bands above the new Nyquist frequency (samp_rate/2/decimation_factor), e.g. by applying a lowpass filter beforehand! New sampling rate is old sampling rate divided by decimation_factor. :type data: numpy.ndarray :param data: Data to filter. :param decimation_factor: Integer decimation factor :return: Downsampled data (array length: old length / decimation_factor) """

    if not isinstance(decimation_factor, int):
        msg = "Decimation_factor must be an integer!"
        raise TypeError(msg)

    # reshape and only use every decimation_factor-th sample
    data = np.array(data[::decimation_factor])
    return data