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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 import_variables(self, container, varnames=None):
 """Helper method to avoid call get_variable for every variable."""

        if varnames is None:
            for keyword in self.tkvariables:
                setattr(container, keyword, self.tkvariables[keyword])
        else:
            for keyword in varnames:
                if keyword in self.tkvariables:
                    setattr(container, keyword, self.tkvariables[keyword])