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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 _varname(self):
 """ Set up variable names in ``self.system.varname``. Variable names follows the convention ``VariableName,Model Name``. A maximum of 24 characters are allowed for each variable. :return: None """

        if not self._flags['address']:
            self.log('Unable to assign Varname before allocating address',
                     ERROR)
            return

        varname = self.system.varname
        for i in range(self.n):
            iname = str(self.name[i])

            for e, var in enumerate(self._states):
                unamex = self._unamex[e]
                fnamex = self._fnamex[e]
                idx = self.__dict__[var][i]

                varname.unamex[idx] = '{} {}'.format(unamex, iname)[:33]
                varname.fnamex[idx] = '$' + '{}\\ {}'.format(
                    fnamex, iname.replace(' ', '\\ '))[:33] + '$'

            for e, var in enumerate(self._algebs):
                unamey = self._unamey[e]
                fnamey = self._fnamey[e]
                idx = self.__dict__[var][i]

                varname.unamey[idx] = '{} {}'.format(unamey, iname)[:33]
                varname.fnamey[idx] = '$' + '{}\\ {}'.format(
                    fnamey, iname.replace(' ', '\\ '))[:33] + '$'