For loading data in a python package, there's a handy utility in pkg_resources which makes it easy to load data relative to python modules, see: http://pythonhosted.org/distribute/pkg_resources.html#basic-resource-access

Your loading code here would then become:

    from pkg_resources import resource_stream
    file_dict = json.load(resource_stream(__name__, 'data/edw_file/' + EDW_TEST_FILE))

(__name__ is the dotted python path of the current module, so 'encoded.tests.test_edw_file' here.)