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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 _init_lsr(n_items, alpha, initial_params):
 """Initialize the LSR Markov chain and the weights."""

    if initial_params is None:
        weights = np.ones(n_items)
    else:
        weights = exp_transform(initial_params)
    chain = alpha * np.ones((n_items, n_items), dtype=float)
    return weights, chain