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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 array_sha256(a):
 """Create a SHA256 hash from a Numpy array."""

    dtype = str(a.dtype).encode()
    shape = numpy.array(a.shape)
    sha = hashlib.sha256()
    sha.update(dtype)
    sha.update(shape)
    sha.update(a.tobytes())
    return sha.hexdigest()