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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 ensure_ndarray_or_None(A, shape=None, uniform=None, ndim=None, size=None, dtype=None, kind=None):
 r""" Ensures A is None or an ndarray and does an assert_array with the given parameters """

    if A is not None:
        return ensure_ndarray(A, shape=shape, uniform=uniform, ndim=ndim, size=size, dtype=dtype, kind=kind)
    else:
        return None