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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 froms(self):
 """Group metrics according to the `from` property. """

        eax = {}
        for name, config in six.iteritems(self._metrics):
            from_ = self._get_property(config, 'from', default=self.stdout)
            eax.setdefault(from_, {})[name] = config
        return eax