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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 np_hash(a):
 """Return a hash of a NumPy array."""

    if a is None:
        return hash(None)
    # Ensure that hashes are equal whatever the ordering in memory (C or
    # Fortran)
    a = np.ascontiguousarray(a)
    # Compute the digest and return a decimal int
    return int(hashlib.sha1(a.view(a.dtype)).hexdigest(), 16)