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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 ExpandDims(a, dim):
 """ Expand dim op, i.e. add singular axis at dim. """

    shape = list(a.shape)
    if dim >= 0:
        shape.insert(dim, 1)
    else:
        shape.insert(len(shape) + dim + 1, 1)
    return np.copy(a).reshape(*shape),