link parent can be str
@@ -88,9 +88,9 @@ class ELink(Link):
# if isinstance(parent, list):
# raise TypeError(
# 'Only one parent link can be present')
- if not isinstance(parent, ELink) and parent is not None:
+ if not isinstance(parent, (ELink, str)) and parent is not None:
raise TypeError(
- 'Parent must be of type ELink')
+ 'Parent must be of type ELink, str or None')
self._parent = parent
self._children = []
