Source code for composer.utils.import_helpers
# Copyright 2021 MosaicML. All Rights Reserved.
"""Dynamically import a Python object (e.g. module, class, function, ...)."""
import importlib
import textwrap
from typing import Any, Optional
__all__ = ["import_object", "MissingConditionalImportError"]
class MissingConditionalImportError(ImportError):
def __init__(self, extra_deps_group: str, conda_package: str, conda_channel: Optional[str] = 'conda-forge'):
"""Handles errors for external packages that might not be installed.
Args:
extra_deps_group (str): the pip package group, found in setup.py. For example, nlp for `mosaicml[nlp]`.
conda_package (str): the conda packages to install.
conda_channel (Optional[str]): the conda channel to install packages from.
Raises: ImportError
"""
super().__init__(
textwrap.dedent(f"""\
Composer was installed without {extra_deps_group} support. To use {extra_deps_group} related packages, with Composer, run `pip install mosaicml[{extra_deps_group}]`
if using pip or `conda install -c {conda_channel} {conda_package} if using Anaconda."""))
[docs]def import_object(name: str) -> Any:
"""Dynamically import a Python object (e.g. class, function, ...).
.. note::
To dynamically import a module, use :func:`importlib.import_module`.
Args:
name (str): The path to the Python object to import.
Separate the module name and class name with a ``':'`` (e.g. ``'path.to.module:function_name'``).
Example:
>>> from composer.utils import import_object
>>> import_object('functools:partial')
<class 'functools.partial'>
.. note::
The module name must be discoverale with the Python path, as determined by :attr:`sys.path`.
Returns:
Any: The imported object.
"""
module_name, object_name = name.split(":")
module = importlib.import_module(module_name)
return getattr(module, object_name)