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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 valarray(shape, value=np.NaN, typecode=None):
 """Return an array of all value."""

    if typecode is None:
        typecode = bool
    out = np.ones(shape, dtype=typecode) * value

    if not isinstance(out, np.ndarray):
        out = np.asarray(out)
    return out