<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_td_waveform(template=None, **kwargs):
 """Return the plus and cross polarizations of a time domain waveform. Parameters template: object An object that has attached properties. This can be used to subsitute for keyword arguments. A common example would be a row in an xml table. {params} Returns ------- hplus: TimeSeries The plus polarization of the waveform. hcross: TimeSeries The cross polarization of the waveform. """

    input_params = props(template, required_args=td_required_args, **kwargs)
    wav_gen = td_wav[type(_scheme.mgr.state)]
    if input_params['approximant'] not in wav_gen:
        raise ValueError("Approximant %s not available" %
                            (input_params['approximant']))
    return wav_gen[input_params['approximant']](**input_params)