Spaces:
Sleeping
Sleeping
| # Copyright (c) Facebook, Inc. and its affiliates. | |
| """ Utilities for developers only. | |
| These are not visible to users (not automatically imported). And should not | |
| appeared in docs.""" | |
| # adapted from https://github.com/tensorpack/tensorpack/blob/master/tensorpack/utils/develop.py | |
| def create_dummy_class(klass, dependency, message=""): | |
| """ | |
| When a dependency of a class is not available, create a dummy class which throws ImportError | |
| when used. | |
| Args: | |
| klass (str): name of the class. | |
| dependency (str): name of the dependency. | |
| message: extra message to print | |
| Returns: | |
| class: a class object | |
| """ | |
| err = "Cannot import '{}', therefore '{}' is not available.".format(dependency, klass) | |
| if message: | |
| err = err + " " + message | |
| class _DummyMetaClass(type): | |
| # throw error on class attribute access | |
| def __getattr__(_, __): # noqa: B902 | |
| raise ImportError(err) | |
| class _Dummy(object, metaclass=_DummyMetaClass): | |
| # throw error on constructor | |
| def __init__(self, *args, **kwargs): | |
| raise ImportError(err) | |
| return _Dummy | |
| def create_dummy_func(func, dependency, message=""): | |
| """ | |
| When a dependency of a function is not available, create a dummy function which throws | |
| ImportError when used. | |
| Args: | |
| func (str): name of the function. | |
| dependency (str or list[str]): name(s) of the dependency. | |
| message: extra message to print | |
| Returns: | |
| function: a function object | |
| """ | |
| err = "Cannot import '{}', therefore '{}' is not available.".format(dependency, func) | |
| if message: | |
| err = err + " " + message | |
| if isinstance(dependency, (list, tuple)): | |
| dependency = ",".join(dependency) | |
| def _dummy(*args, **kwargs): | |
| raise ImportError(err) | |
| return _dummy | |