[Refactor] Auto fix view.py. (#4461)

Co-authored-by: Ubuntu <ubuntu@ip-172-31-34-29.ap-northeast-1.compute.internal>
Co-authored-by: Minjie Wang <wmjlyjemaine@gmail.com>

python/dgl/view.py

@@ -11,6 +11,7 @@ from .frame import LazyFeature
 NodeSpace = namedtuple('NodeSpace', ['data'])
 EdgeSpace = namedtuple('EdgeSpace', ['data'])
 
+
 class HeteroNodeView(object):
     """A NodeView class to act as G.nodes for a DGLHeteroGraph."""
     __slots__ = ['_graph', '_typeid_getter']
@@ -36,7 +37,9 @@ class HeteroNodeView(object):
             nodes = key
             ntype = None
         ntid = self._typeid_getter(ntype)
-        return NodeSpace(data=HeteroNodeDataView(self._graph, ntype, ntid, nodes))
+        return NodeSpace(
+            data=HeteroNodeDataView(
+                self._graph, ntype, ntid, nodes))
 
     def __call__(self, ntype=None):
         """Return the nodes."""
@@ -45,6 +48,7 @@ class HeteroNodeView(object):
                        dtype=self._graph.idtype, ctx=self._graph.device)
         return ret
 
+
 class HeteroNodeDataView(MutableMapping):
     """The data view class when G.ndata[ntype] is called."""
     __slots__ = ['_graph', '_ntype', '_ntid', '_nodes']
@@ -59,7 +63,9 @@ class HeteroNodeDataView(MutableMapping):
         if isinstance(self._ntype, list):
             ret = {}
             for (i, ntype) in enumerate(self._ntype):
-                value = self._graph._get_n_repr(self._ntid[i], self._nodes).get(key, None)
+                value = self._graph._get_n_repr(
+                    self._ntid[i], self._nodes).get(
+                    key, None)
                 if value is not None:
                     ret[ntype] = value
             return ret
@@ -76,12 +82,12 @@ class HeteroNodeDataView(MutableMapping):
 
             for (ntype, data) in val.items():
                 ntid = self._graph.get_ntype_id(ntype)
-                self._graph._set_n_repr(ntid, self._nodes, {key : data})
+                self._graph._set_n_repr(ntid, self._nodes, {key: data})
         else:
             assert isinstance(val, dict) is False, \
                 'The HeteroNodeDataView has only one node type. ' \
                 'please pass a tensor directly'
-            self._graph._set_n_repr(self._ntid, self._nodes, {key : val})
+            self._graph._set_n_repr(self._ntid, self._nodes, {key: val})
 
     def __delitem__(self, key):
         if isinstance(self._ntype, list):
@@ -102,7 +108,8 @@ class HeteroNodeDataView(MutableMapping):
         else:
             ret = self._graph._get_n_repr(self._ntid, self._nodes)
             if as_dict:
-                ret = {key: ret[key] for key in self._graph._node_frames[self._ntid]}
+                ret = {key: ret[key]
+                       for key in self._graph._node_frames[self._ntid]}
         return ret
 
     def __len__(self):
@@ -120,6 +127,7 @@ class HeteroNodeDataView(MutableMapping):
     def __repr__(self):
         return repr(self._transpose(as_dict=True))
 
+
 class HeteroEdgeView(object):
     """A EdgeView class to act as G.edges for a DGLHeteroGraph."""
     __slots__ = ['_graph']
@@ -157,6 +165,7 @@ class HeteroEdgeView(object):
         """Return all the edges."""
         return self._graph.all_edges(*args, **kwargs)
 
+
 class HeteroEdgeDataView(MutableMapping):
     """The data view class when G.edata[etype] is called."""
     __slots__ = ['_graph', '_etype', '_etid', '_edges']
@@ -173,7 +182,9 @@ class HeteroEdgeDataView(MutableMapping):
         if isinstance(self._etype, list):
             ret = {}
             for (i, etype) in enumerate(self._etype):
-                value = self._graph._get_e_repr(self._etid[i], self._edges).get(key, None)
+                value = self._graph._get_e_repr(
+                    self._etid[i], self._edges).get(
+                    key, None)
                 if value is not None:
                     ret[etype] = value
             return ret
@@ -190,12 +201,12 @@ class HeteroEdgeDataView(MutableMapping):
 
             for (etype, data) in val.items():
                 etid = self._graph.get_etype_id(etype)
-                self._graph._set_e_repr(etid, self._edges, {key : data})
+                self._graph._set_e_repr(etid, self._edges, {key: data})
         else:
             assert isinstance(val, dict) is False, \
                 'The HeteroEdgeDataView has only one edge type. ' \
                 'please pass a tensor directly'
-            self._graph._set_e_repr(self._etid, self._edges, {key : val})
+            self._graph._set_e_repr(self._etid, self._edges, {key: val})
 
     def __delitem__(self, key):
         if isinstance(self._etype, list):
@@ -216,7 +227,8 @@ class HeteroEdgeDataView(MutableMapping):
         else:
             ret = self._graph._get_e_repr(self._etid, self._edges)
             if as_dict:
-                ret = {key: ret[key] for key in self._graph._edge_frames[self._etid]}
+                ret = {key: ret[key]
+                       for key in self._graph._edge_frames[self._etid]}
         return ret
 
     def __len__(self):