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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 _auth(self, user, password):
 """ authenticate a user @str user: login of the user @str password: password of the user @rtype: dict, {'connected': <boolean, True if connection succeded>, 'isadmin': <True if user is ldapcherry administrator>} """

        if self.auth_mode == 'none':
            return {'connected': True, 'isadmin': True}
        elif self.auth_mode == 'and':
            ret1 = True
            for b in self.backends:
                ret1 = self.backends[b].auth(user, password) and ret1
        elif self.auth_mode == 'or':
            ret1 = False
            for b in self.backends:
                ret1 = self.backends[b].auth(user, password) or ret1
        elif self.auth_mode == 'custom':
            ret1 = self.auth.auth(user, password)
        else:
            raise Exception()
        if not ret1:
            return {'connected': False, 'isadmin': False}
        else:
            isadmin = self._is_admin(user)
            return {'connected': True, 'isadmin': isadmin}