### Summary

Add type hints to `ansible.parsing.dataloader::DataLoader`

### Issue Type

Feature Idea

### Component Name

lib/ansible/parsing/dataloader.py
''' returns the current basedir '''
        return self._basedir
    def set_basedir(self, basedir):
        ''' sets the base directory, used to find files when a relative path is given '''
        if basedir is not None:
            self._basedir = to_text(basedir)
    def path_dwim(self, given):
        '''
        make relative paths work like folks expect.
        '''
        given = unquote(given)
        given = to_text(given, errors='surrogate_or_strict')
        if given.startswith(to_text(os.path.sep)) or given.startswith(u'~'):
            path = given
        else:
            basedir = to_text(self._basedir, errors='surrogate_or_strict')
            path = os.path.join(basedir, given)
        return unfrackpath(path, follow=False)
    def _is_role(self, path):