'doctest_module_item_cls should be a class inheriting
`pytest.doctest.DoctestItem` and `pytest.File`.  This class handles
running of a single doctest found in a Python module.  This is passed
in as an argument because the actual class to be used may not be
available at import time, depending on whether or not the doctest
plugin for py.test is available.'

def __init__(self, doctest_module_item_cls, doctest_textfile_item_cls, run_rst_doctests):

    self._doctest_module_item_cls = doctest_module_item_cls
    self._doctest_textfile_item_cls = doctest_textfile_item_cls
    self._run_rst_doctests = run_rst_doctests
    self._ignore_paths = []
