super-gradients/src/super_gradients/training/exceptions/sg_trainer_exceptions.py

class UnsupportedTrainingParameterFormat(Exception):
    """Exception raised illegal training param format.

    Attributes:
        message -- explanation of the error
    """

    def __init__(self, desc):
        self.message = "Unsupported training parameter format: " + desc
        super().__init__(self.message)


class UnsupportedOptimizerFormat(UnsupportedTrainingParameterFormat):
    """Exception raised illegal optimizer format.

    Attributes:
        message -- explanation of the error
    """

    def __init__(self):
        super().__init__(
            "optimizer parameter expected one of ['Adam','SGD','RMSProp'], or torch.optim.Optimizer object")


class IllegalDataloaderInitialization(Exception):
    """Exception raised illegal data loaders.
    """

    def __init__(self):
        super().__init__(
            "train_loader, valid_loader and class parameters are required when initializing Trainer with data loaders")


class GPUModeNotSetupError(Exception):
    """Exception raised when the DDP should be setup but is not.
    """

    def __init__(self):
        super().__init__("Your environment was not setup to support DDP. Please run at the beginning of your script:\n"
                         ">>> from super_gradients.common.environment.env_helpers import init_trainer\n"
                         ">>> setup_gpu_mode(gpu_mode=..., num_gpus=...)\n")