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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 _zeropad(sig, N, axis=0):
 """pads with N zeros at the end of the signal, along given axis"""

    # ensures concatenation dimension is the first
    sig = np.moveaxis(sig, axis, 0)
    # zero pad
    out = np.zeros((sig.shape[0] + N,) + sig.shape[1:])
    out[:sig.shape[0], ...] = sig
    # put back axis in place
    out = np.moveaxis(out, 0, axis)
    return out