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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_groups(self, username):
 """Get all groups of a user"""

        username = ldap.filter.escape_filter_chars(self._byte_p2(username))
        userdn = self._get_user(username, NO_ATTR)

        searchfilter = self.group_filter_tmpl % {
            'userdn': userdn,
            'username': username
        }

        groups = self._search(searchfilter, NO_ATTR, self.groupdn)
        ret = []
        for entry in groups:
            ret.append(self._uni(entry[0]))
        return ret