optimized imports

charge/chargers.py

@@ -31,8 +31,7 @@ def __init__(self,
 
         Args:
             repository: The repository to obtain charges from
-            rounding_digits: Number of significant digits to round
-                    charges to.
+            rounding_digits: Number of significant digits to round charges to.
             nauty: An external Nauty instance to use for canonization
         """
         # These are all protected, not private

charge/molecule.py

@@ -1,8 +1,9 @@
-import networkx as nx
 from typing import Generator, Tuple
 
-from charge.nauty import  Nauty
+import networkx as nx
+
 from charge.charge_types import Atom
+from charge.nauty import Nauty
 
 
 def atoms_neighborhoods_charges(

charge/multiprocessor.py

@@ -1,11 +1,11 @@
 import multiprocessing as mp
-import os
 import sys
 import traceback
 from typing import Any, Generator, List, Tuple, Type
 
 from charge.util import print_progress
 
+
 class _Stop:
     pass
 

charge/nauty.py

@@ -10,7 +10,6 @@
 from charge.settings import NAUTY_EXC
 from charge.util import bfs_nodes
 
-
 Color = Tuple[bool, str]
 """Nodes are colored by whether they are the core node, and then by atom type."""
 

charge/test/conftest.py

@@ -1,12 +1,13 @@
 from collections import defaultdict
-import networkx as nx
-import os
 from pathlib import Path
+
+import networkx as nx
 import pytest
 
 from charge.bond_type import BondType
 from charge.nauty import Nauty
 
+
 # Fixtures for testing loading and saving to and from various
 # formats.
 
@@ -185,7 +186,6 @@ def ref_graph_rdkit(ref_graph_nodes, ref_graph_edges):
 
 @pytest.fixture
 def ref_graph_nodes_shifted(ref_graph_nodes):
-    from rdkit import Chem
     return [(v-1, data) for v, data in ref_graph_nodes]
 
 

charge/test/test_babel.py

@@ -1,10 +1,9 @@
-import pytest
-
-import networkx as nx
 import networkx.algorithms.isomorphism as nxiso
+import pytest
 
 from charge.babel import convert_from, IOType, convert_to
 
+
 def equal_attributes(att1, att2):
      return att1 == att2
 

charge/test/test_chargers.py

@@ -1,9 +1,9 @@
-from charge.chargers import CDPCharger, DPCharger, ILPCharger, MeanCharger, MedianCharger, ModeCharger
-
 from math import log
-import networkx as nx
+
 import pytest
 
+from charge.chargers import CDPCharger, DPCharger, ILPCharger, MeanCharger, MedianCharger, ModeCharger
+
 
 def test_mean_charger(mock_repository, ref_graph):
     charger = MeanCharger(mock_repository, 2)

charge/test/test_collectors.py

@@ -1,9 +1,9 @@
-from charge.collectors import AssignmentError, HistogramCollector, MeanCollector
-
 from math import log
-import networkx as nx
+
 import pytest
 
+from charge.collectors import AssignmentError, HistogramCollector, MeanCollector
+
 
 def test_mean_collector(ref_graph, mock_repository):
     collector = MeanCollector(mock_repository, 2)

charge/test/test_nauty.py

@@ -1,9 +1,9 @@
-from pathlib import Path
-import pytest
 import stat
+from pathlib import Path
 
 from charge.nauty import Nauty
 
+
 def test_create():
     nauty = Nauty()
     assert nauty.exe != ''

charge/test/test_repository.py

@@ -1,5 +1,3 @@
-import pytest
-
 from charge.repository import Repository
 
 def test_create_empty():

charge/test/test_solvers.py

@@ -1,8 +1,7 @@
-from charge.solvers import CDPSolver, DPSolver, ILPSolver, SimpleSolver
-
-import networkx as nx
 import pytest
 
+from charge.solvers import CDPSolver, DPSolver, ILPSolver, SimpleSolver
+
 
 def test_simple_solver(ref_graph):
     solver = SimpleSolver(2)

scripts/build_repo.py

@@ -1,9 +1,7 @@
 import os
-import warnings
 
 from charge.repository import Repository
 
-
 if __name__ == '__main__':
 
     test_data_dir = os.path.realpath(