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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 as_square_array(arr):
 """Return arr massaged into a square array. Raises ValueError if arr cannot be so massaged. """

    arr = np.atleast_2d(arr)
    if len(arr.shape) != 2 or arr.shape[0] != arr.shape[1]:
        raise ValueError("Expected square array")
    return arr