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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 set_maxrad(self,newrad):
 """ Sets max allowed radius in populations. Doesn't operate via the :class:`stars.Constraint` protocol; rather just rescales the sky positions for the background objects and recalculates sky area, etc. """

        if not isinstance(newrad, Quantity):
            newrad = newrad * u.arcsec
        #if 'Rsky' not in self.constraints:
        #    self.constraints.append('Rsky')
        for pop in self.poplist:
            if not pop.is_specific:
                try:
                    pop.maxrad = newrad
                except AttributeError:
                    pass