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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 flip(a, axis):
 """Reverse the order of elements in an array along the given axis. This function is a backport of `numpy.flip` introduced in NumPy 1.12. See Also -------- numpy.flip """

    if not hasattr(a, 'ndim'):
        a = np.asarray(a)
    indexer = [slice(None)] * a.ndim
    try:
        indexer[axis] = slice(None, None, -1)
    except IndexError:
        raise ValueError('axis={} is invalid for the {}-dimensional input '
                         'array'.format(axis, a.ndim))
    return a[tuple(indexer)]