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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 _next_argsig(s):
 """ given a string, find the next complete argument signature and return it and a new string advanced past that point """


    c = s[0]

    if c in "BCDFIJSVZ":
        result = (c, s[1:])

    elif c == "[":
        d, s = _next_argsig(s[1:])
        result = (c + d, s[len(d) + 1:])

    elif c == "L":
        i = s.find(';') + 1
        result = (s[:i], s[i + 1:])

    elif c == "(":
        i = s.find(')') + 1
        result = (s[:i], s[i:])

    else:
        raise Unimplemented("_next_argsig is %r in %r" % (c, s))

    return result