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from importlib import import_module


def import_string(dotted_path):
    """
    Import a dotted module path and return the attribute/class designated by the
    last name in the path. Raise ImportError if the import failed.

    From https://github.com/django/django/blob/master/django/utils/module_loading.py
    """
    try:
        module_path, class_name = dotted_path.rsplit(".", 1)
    except ValueError:
        msg = "%s doesn't look like a module path" % dotted_path
        raise ImportError(msg)

    module = import_module(module_path)

    try:
        return getattr(module, class_name)
    except AttributeError:
        msg = 'Module "%s" does not define a "%s" attribute/class' % (module_path, class_name)
        raise ImportError(msg)