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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 _get_datetimes(self, timestep=1):
 """List of datetimes based on design day date and timestep."""

        start_moy = DateTime(self._month, self._day_of_month).moy
        if timestep == 1:
            start_moy = start_moy + 30
        num_moys = 24 * timestep
        return tuple(
            DateTime.from_moy(start_moy + (i * (1 / timestep) * 60))
            for i in xrange(num_moys)
        )