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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 s_find_first(pred, first, lst):
 """Evaluate `first`; if predicate `pred` succeeds on the result of `first`, return the result; otherwise recur on the first element of `lst`. :param pred: a predicate. :param first: a promise. :param lst: a list of quoted promises. :return: the first element for which predicate is true."""

    if pred(first):
        return first
    elif lst:
        return s_find_first(pred, unquote(lst[0]), lst[1:])
    else:
        return None