def _assert_strides_are_log2_contiguous(strides):
    """
    Assert that each stride is 2x times its preceding stride, i.e. "contiguous in log2".
    """
    for i, stride in enumerate(strides[1:], 1):
        assert stride == 2 * strides[i - 1], "Strides {} {} are not log2 contiguous".format(
            stride, strides[i - 1]
        )

    Assert that each stride is 2x times its preceding stride, i.e. "contiguous in log2".
    
iGPT/models/grit_src/third_party/CenterNet2/projects/CenterNet2/centernet/modeling/backbone/bifpn_fcos.py