def _activations() -> _List[_BackendPatternConfig]:
    """
    float: Act
    qat: FakeQuant -> Act -> FakeQuant
    """
    ops = [op for op in _mod_activations if op not in _fixed_qparams_modules]
    ops += [
        _nn.ReLU,
        _F.relu,
        _F.relu_,
    ] + list(_func_activations)
    return _activation_configs(ops=ops)

    float: Act
    qat: FakeQuant -> Act -> FakeQuant
    
coremltools/optimize/torch/quantization/_backend_config.py