Simplify base classes. (#2604)

* move selfloop methods out of graph classes into function.py

* replace G.node with G.nodes. fix Pickle of views

* Replace G.edge with G.edges

* Add a few lines of docs for release realted to this PR.

4 files changed, 15 insertions, 15 deletions

diff --git a/networkx/readwrite/json_graph/tests/test_adjacency.py b/networkx/readwrite/json_graph/tests/test_adjacency.py
index 06b36830..ca19423b 100644
--- a/networkx/readwrite/json_graph/tests/test_adjacency.py
+++ b/networkx/readwrite/json_graph/tests/test_adjacency.py
@@ -19,14 +19,14 @@ class TestAdjacency:
 
         H = adjacency_graph(adjacency_data(G))
         assert_equal(H.graph['foo'],'bar')
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
         assert_equal(H[1][2]['width'],7)
 
         d = json.dumps(adjacency_data(G))
         H = adjacency_graph(json.loads(d))
         assert_equal(H.graph['foo'],'bar')
         assert_equal(H.graph[1],'one')
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
         assert_equal(H[1][2]['width'],7)
 
     def test_digraph(self):
diff --git a/networkx/readwrite/json_graph/tests/test_cytoscape.py b/networkx/readwrite/json_graph/tests/test_cytoscape.py
index 6907071c..639f87e1 100644
--- a/networkx/readwrite/json_graph/tests/test_cytoscape.py
+++ b/networkx/readwrite/json_graph/tests/test_cytoscape.py
@@ -20,20 +20,20 @@ class TestCytoscape:
         
         H = cytoscape_graph(cytoscape_data(G))
         assert_equal(H.graph['foo'],'bar')
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
         assert_equal(H[1][2]['width'],7)
-        assert_equal(H.node[3]['name'],'node')
-        assert_equal(H.node[3]['id'],'123')
+        assert_equal(H.nodes[3]['name'],'node')
+        assert_equal(H.nodes[3]['id'],'123')
         
 
         d = json.dumps(cytoscape_data(G))
         H = cytoscape_graph(json.loads(d))
         assert_equal(H.graph['foo'],'bar')
         assert_equal(H.graph[1],'one')
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
         assert_equal(H[1][2]['width'],7)
-        assert_equal(H.node[3]['name'],'node')
-        assert_equal(H.node[3]['id'],'123')
+        assert_equal(H.nodes[3]['name'],'node')
+        assert_equal(H.nodes[3]['id'],'123')
         
         
         
diff --git a/networkx/readwrite/json_graph/tests/test_node_link.py b/networkx/readwrite/json_graph/tests/test_node_link.py
index f1068cf9..870b7e8d 100644
--- a/networkx/readwrite/json_graph/tests/test_node_link.py
+++ b/networkx/readwrite/json_graph/tests/test_node_link.py
@@ -21,14 +21,14 @@ class TestNodeLink:
 
         H = node_link_graph(node_link_data(G))
         assert_equal(H.graph['foo'], 'bar')
-        assert_equal(H.node[1]['color'], 'red')
+        assert_equal(H.nodes[1]['color'], 'red')
         assert_equal(H[1][2]['width'], 7)
 
         d = json.dumps(node_link_data(G))
         H = node_link_graph(json.loads(d))
         assert_equal(H.graph['foo'], 'bar')
         assert_equal(H.graph['1'], 'one')
-        assert_equal(H.node[1]['color'], 'red')
+        assert_equal(H.nodes[1]['color'], 'red')
         assert_equal(H[1][2]['width'], 7)
 
     def test_digraph(self):
@@ -51,7 +51,7 @@ class TestNodeLink:
         dumped_d = json.dumps(d)
         dd = json.loads(dumped_d)
         H = node_link_graph(dd)
-        assert_equal(H.node[(0, 0)], G.node[(0, 0)])
+        assert_equal(H.nodes[(0, 0)], G.nodes[(0, 0)])
         assert_equal(H[(0, 0)][(1, 0)]['color'], [255, 255, 0])
 
     def test_unicode_keys(self):
@@ -65,7 +65,7 @@ class TestNodeLink:
         output = json.dumps(s, ensure_ascii=False)
         data = json.loads(output)
         H = node_link_graph(data)
-        assert_equal(H.node[1][q], q)
+        assert_equal(H.nodes[1][q], q)
 
     @raises(nx.NetworkXError)
     def test_exception(self):
@@ -101,6 +101,6 @@ class TestNodeLink:
         H = node_link_graph(node_link_data(G, attrs=attrs), multigraph=False, attrs=attrs)
         assert_true(nx.is_isomorphic(G, H))
         assert_equal(H.graph['foo'], 'bar')
-        assert_equal(H.node[1]['color'], 'red')
+        assert_equal(H.nodes[1]['color'], 'red')
         assert_equal(H[1][2]['width'], 7)
 
diff --git a/networkx/readwrite/json_graph/tests/test_tree.py b/networkx/readwrite/json_graph/tests/test_tree.py
index 659c4d8f..c69a3143 100644
--- a/networkx/readwrite/json_graph/tests/test_tree.py
+++ b/networkx/readwrite/json_graph/tests/test_tree.py
@@ -21,11 +21,11 @@ class TestTree:
         G.add_edge(1,3,foo=10)
         G.add_edge(3,4,foo=10)
         H = tree_graph(tree_data(G,1))
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
 
         d = json.dumps(tree_data(G,1))
         H = tree_graph(json.loads(d))
-        assert_equal(H.node[1]['color'],'red')
+        assert_equal(H.nodes[1]['color'],'red')
 
     @raises(nx.NetworkXError)
     def test_exception(self):