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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 cdot(L, out=None):
 r"""Product of a Cholesky matrix with itself transposed. Args: L (array_like):
 Cholesky matrix. out (:class:`numpy.ndarray`, optional):
 copy result to. Returns: :class:`numpy.ndarray`: :math:`\mathrm L\mathrm L^\intercal`. """

    L = asarray(L, float)

    layout_error = "Wrong matrix layout."

    if L.ndim != 2:
        raise ValueError(layout_error)

    if L.shape[0] != L.shape[1]:
        raise ValueError(layout_error)

    if out is None:
        out = empty((L.shape[0], L.shape[1]), float)

    return einsum("ij,kj->ik", L, L, out=out)