Get parents recursively

Summary

Entity.get_parents_recursively() did not work for unretrieved parents. Does work now. See #159 (closed).

Focus

• Does this solve the issue?
• Is the wrapped-entity mangling the correct way? (If not, how could tests against this look like?)

Test Environment

See pyinttests: pytest-3 -k recurs or pytest-3 tests/test_recursive_parents.py

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src/caosdb/common/models.py

@@ -112,7 +112,7 @@ class Entity:
         self.value = value
         self.messages = _Messages()
         self.properties = _Properties()
-        self.parents = _Parents()
+        self.parents = _ParentList()
         self.path = None
         self.file = None
         self.unit = None
@@ -680,7 +680,7 @@ out: bool
     def get_parents(self):
         """Get all parents of this entity.
 
-        @return: _Parents(list)
+        @return: _ParentList(list)
         """
 
         return self.parents
@@ -2129,7 +2129,8 @@ class _Properties(list):
         raise KeyError(str(prop) + " not found.")
 
 
-class _Parents(list):
+class _ParentList(list):
+    # TODO unclear why this class is private. Isn't it use full for users?
 
     def _get_entity_by_cuid(self, cuid):
         '''