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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 check_time_only(time, signal, verb):
 r"""Check time and signal parameters. This check-function is called from one of the modelling routines in :mod:`model`. Consult these modelling routines for a detailed description of the input parameters. Parameters time : array_like Times t (s). signal : {None, 0, 1, -1} Source signal: - None: Frequency-domain response - -1 : Switch-off time-domain response - 0 : Impulse time-domain response - +1 : Switch-on time-domain response verb : {0, 1, 2, 3, 4} Level of verbosity. Returns ------- time : float Time, checked for size and assured min_time. """

    global _min_time

    # Check input signal
    if int(signal) not in [-1, 0, 1]:
        print("* ERROR   :: <signal> must be one of: [None, -1, 0, 1]; " +
              "<signal> provided: "+str(signal))
        raise ValueError('signal')

    # Check time
    time = _check_var(time, float, 1, 'time')

    # Minimum time to avoid division by zero  at time = 0 s.
    # => min_time can be set with utils.set_min
    time = _check_min(time, _min_time, 'Times', 's', verb)
    if verb > 2:
        _prnt_min_max_val(time, "   time        [s] : ", verb)

    return time