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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 space_shape(space):
 """Return ``space.shape``, including power space base shape. If ``space`` is a power space, return ``(len(space),) + space[0].shape``, otherwise return ``space.shape``. """

    if isinstance(space, odl.ProductSpace) and space.is_power_space:
        return (len(space),) + space[0].shape
    else:
        return space.shape