def insert_element_to_dict_of_list(dict_of_list, key, parser):
if key in dict_of_list.keys():<EOL><INDENT>dict_of_list[key].append(parser)<EOL><DEDENT>else:<EOL><INDENT>dict_of_list[key] = [parser]<EOL><DEDENT>
Utility method

:param dict_of_list:
:param key:
:param parser:
:return: