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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 get_entry_map(self, group=None):
 """Return the entry point map for `group`, or the full entry map"""

        try:
            ep_map = self._ep_map
        except AttributeError:
            ep_map = self._ep_map = EntryPoint.parse_map(
                self._get_metadata('entry_points.txt'), self
            )
        if group is not None:
            return ep_map.get(group, {})
        return ep_map