fix lint error

pyscfad/cc/ccsd_t.py

@@ -1,7 +1,7 @@
 import ctypes
 import numpy
 from jax import custom_vjp
 from jax.tree_util import tree_flatten_with_path, tree_unflatten
 from pyscf.lib import (
     prange_tril,
     num_threads,
@@ -35,31 +35,31 @@
         eris, t1, t2 = res
 
         # TODO clean up tree unflatten
         path_vals, treedef = tree_flatten_with_path(eris)
         keys = [item[0][0].name for item in path_vals]
         shapes = [item[1].shape for item in path_vals]
         path_vals = None
 
         t1_bar, t2_bar, fock_bar, mo_energy_bar,\
             ovoo_bar, ovov_bar, ovvv_bar = _ccsd_t_energy_vjp(eris, t1, t2, ybar, max_memory)
 
         leaves = [None] * len(keys)
         key_to_bar = {
-            "fock": fock_bar,
-            "mo_energy": mo_energy_bar,
-            "ovoo": ovoo_bar,
-            "ovov": ovov_bar,
-            "ovvv": ovvv_bar,
+            'fock': fock_bar,
+            'mo_energy': mo_energy_bar,
+            'ovoo': ovoo_bar,
+            'ovov': ovov_bar,
+            'ovvv': ovvv_bar,
         }
 
         for k, val in key_to_bar.items():
             leaves[keys.index(k)] = val
 
         for i, leaf in enumerate(leaves):
             if leaf is None:
                 leaves[i] = numpy.zeros(shapes[i])
 
         eris_bar = tree_unflatten(treedef, leaves)
         return eris_bar, t1_bar, t2_bar
 
     _ccsd_t_kernel.defvjp(_ccsd_t_kernel_fwd, _ccsd_t_kernel_bwd)