diff --git a/pyscf/__init__.py b/pyscf/__init__.py
index 5496fe1058..12991c7777 100644
--- a/pyscf/__init__.py
+++ b/pyscf/__init__.py
@@ -21,7 +21,7 @@
 ----------
 There are two ways to access the documentation: the docstrings come with
 the code, and an online program reference, available from
-http://www.sunqm.net/pyscf/index.html
+http://www.pyscf.org
 
 We recommend the enhanced Python interpreter `IPython <http://ipython.org>`_
 and the web-based Python IDE `Ipython notebook <http://ipython.org/notebook.html>`_
diff --git a/pyscf/gto/pp_int.py b/pyscf/gto/pp_int.py
index 4034b7b88f..c94c73c5c7 100644
--- a/pyscf/gto/pp_int.py
+++ b/pyscf/gto/pp_int.py
@@ -40,7 +40,6 @@ def get_gth_pp(mol):
 
     intors = ('int3c2e', 'int3c1e', 'int3c1e_r2_origk',
               'int3c1e_r4_origk', 'int3c1e_r6_origk')
-    fake_cells = {}
     for cn in range(1, 5):
         fakemol = pp_int.fake_cell_vloc(mol, cn)
         if fakemol.nbas > 0:
diff --git a/pyscf/pbc/scf/test/test_hf.py b/pyscf/pbc/scf/test/test_hf.py
index aaa19b0893..b4f05eff2e 100644
--- a/pyscf/pbc/scf/test/test_hf.py
+++ b/pyscf/pbc/scf/test/test_hf.py
@@ -260,7 +260,7 @@ def test_ghf_exx_ewald(self):
     def test_rhf_0d(self):
         cell = pbcgto.Cell()
         cell.build(unit = 'B',
-                   a = np.eye(3)*5,
+                   a = numpy.eye(3)*5,
                    atom = '''He 2 2 2; He 2 2 3''',
                    dimension = 0,
                    verbose = 0,
@@ -292,7 +292,7 @@ def test_rhf_0d(self):
          0.32235865    2     2.25670239    -0.39677748
                                             0.93894690
                                                      ''')}
-        cell.a = np.eye(3)
+        cell.a = numpy.eye(3)
         cell.dimension = 0
         cell.build()
         mf = pbcscf.RHF(cell)
diff --git a/pyscf/scf/_vhf.py b/pyscf/scf/_vhf.py
index 697b6b87ee..bd39196577 100644
--- a/pyscf/scf/_vhf.py
+++ b/pyscf/scf/_vhf.py
@@ -399,7 +399,6 @@ def incore(eri, dms, hermi=0, with_j=True, with_k=True):
 # direct_mapdm
 def direct(dms, atm, bas, env, vhfopt=None, hermi=0, cart=False,
            with_j=True, with_k=True, out=None, optimize_sr=False):
-    omega = env[gto.PTR_RANGE_OMEGA]
     dms = numpy.asarray(dms, order='C', dtype=numpy.double)
     dms_shape = dms.shape
     nao = dms_shape[-1]