adds a workaround to access nodes with node

The current workaround in networkx was removed which enabled access
of nodes with the node attribute. This commit adds the workaround
in uesgraphs.

uesgraphs/uesgraph.py

@@ -121,6 +121,10 @@ def __init__(self):
         self.simplification_level = 0
         self.pipeIDs = []
 
+    @property
+    def node(self):
+        return self.nodes
+
     @property
     def positions(self):
         for node in self.nodes(data=True):