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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 _full_to_yearly_ts(self, arr, dt):
 """Average the full timeseries within each year."""

        time_defined = self.def_time and not ('av' in self.dtype_in_time)
        if time_defined:
            arr = utils.times.yearly_average(arr, dt)
        return arr