Fix typo.

src/decagon_pytorch/normalize.py

@@ -37,7 +37,7 @@ def normalize_adjacency_matrix(adj):
 
 def norm_adj_mat_one_node_type(adj):
     adj = sp.coo_matrix(adj)
-    assert adj.shape[0] == adj.shape[1]:
+    assert adj.shape[0] == adj.shape[1]
     adj_ = adj + sp.eye(adj.shape[0])
     rowsum = np.array(adj_.sum(1))
     degree_mat_inv_sqrt = np.power(rowsum, -0.5).flatten()