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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 which_epi_janus_resonance(name, time):
 """Find which swap situtation we are in by time. Starting from 2006-01-21 where a Janus-Epimetheus swap occured, and defining the next 4 years until the next swap as `scenario1, and the 4 years after that `scenario2`. Calculate in units of 4 years, in which scenario the given time falls. Parameters time : timestring, datetime Time of the image. The astropy Time object can deal with both formats. Returns ------- str The given name string (either `janus` or `epimetheus`) and attach a 1 or 2, as appropriate. """

    t1 = Time('2002-01-21').to_datetime()
    delta = Time(time).to_datetime() - t1
    yearfraction = delta.days / 365
    if int(yearfraction / 4) % 2 == 0:
        return name + '2'
    else:
        return name + '1'