def _is_valid_fast_cat(func_attrs):
    """
    Checks whether the call is acceptable for the concatenate
    kernel in concatenate_fast.py
    """

    if "fast_cat" not in func_attrs:
        return False
    if not func_attrs["fast_cat"]:
        return False
    if len(func_attrs["inputs"]) == 0:
        return False
    return True

    Checks whether the call is acceptable for the concatenate
    kernel in concatenate_fast.py
    
python/aitemplate/backend/cuda/tensor/concatenate.py