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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 formatall(self, *args, **kargs):
        " Add-on method for fits returned by chained_nonlinear_fit. "
        ans = ''
        for x in self.chained_fits:
            ans += 10 * '=' + ' ' + str(x) + '\n'
            ans += self.chained_fits[x].format(*args, **kargs)
            ans += '\n'
        return ans[:-1]