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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 prepare_adiabatic_limit(slh, k=None):
 """Prepare the adiabatic elimination on an SLH object Args: slh: The SLH object to take the limit for k: The scaling parameter $k \rightarrow \infty$. The default is a positive symbol 'k' Returns: tuple: The objects ``Y, A, B, F, G, N`` necessary to compute the limiting system. """

    if k is None:
        k = symbols('k', positive=True)
    Ld = slh.L.dag()
    LdL = (Ld * slh.L)[0, 0]
    K = (-LdL / 2 + I * slh.H).expand().simplify_scalar()
    N = slh.S.dag()
    B, A, Y = K.series_expand(k, 0, 2)
    G, F = Ld.series_expand(k, 0, 1)

    return Y, A, B, F, G, N