imptools

Tools for improving Python imports.

import_path

imptools.import_path(path, name=None, notfound='error', reload=False)[source]

Import a module from any path on the filesystem.

Usually, this would be achieved by adding the parent directory of the module to sys.path or the PYTHONPATH environment variable and then importing it normally. However, this pollutes Python’s import path, which can lead to accidentally importing the wrong modules. The function import_path() avoids this problem by importing a package from a path on the filesystem without modifying the Python import path.

The module can be either a directory containing __init__.py or a single file.

Relative paths are resolved relative to the directory of the source file that calls import_path().

import imptools

my_module = imptools.import_path('../path/to/my_module')

import imptools

my_module = imptools.import_path(
'../path/to/my_module',  # Path to a module directory or single file.
notfound='error',        # Raise 'error' or 'ignore' if not found.
reload=False,            # Whether to import if already available.
)

import my_module  # Import statement also works.

Parameters

path (str or Path) – The filesystem path to the module to import. This should be either a directory containing an __init__.py file or a single file with .py extension. The path can be relative.
name (str, optional) – A name that is compared to the directory name of path and must match it. Useful for relative paths.
notfound (str) – A string indicating what to do if the module is not found. Values can be error to raise an exception or ignore to return None from this function.
reload (bool) – A boolean indicating whether to reload the package if it is already loaded.

Raises

ModuleNotFoundError – If path does not point to a module or if name is specified and dose not match the directory name of path.

Returns

The module or None if it was not found.

enable_relative

imptools.enable_relative()[source]

Enable relative imports for scripts that are not executed as module.

Usually, scripts that are part of a module and use relative imports must be run as python3 -m module.script. However, this requires being in the correct working directory and can be annoying. The enable_relative() function allows to execute those scripts normally as python3 script.py.

Since PEP 366, this can be achieved by setting the __package__ variable in the script and importing the package or making it available on the Pyhton import path. The enable_relative() function hides this behind a simple function that can be imported and called inside the script, before any relative imports.

import imptools

imptools.enable_relative()

# Relative imports...

Raises: ModuleNotFoundError – If the parent directory of the script that calls this function is not a module.