Require isort on all Python files. (#8420)

demo/dask/cpu_survival.py

@@ -4,12 +4,14 @@ Example of training survival model with Dask on CPU
 
 """
 
-import xgboost as xgb
 import os
-from xgboost.dask import DaskDMatrix
+
 import dask.dataframe as dd
-from dask.distributed import Client
-from dask.distributed import LocalCluster
+from dask.distributed import Client, LocalCluster
+from xgboost.dask import DaskDMatrix
+
+import xgboost as xgb
+
 
 def main(client):
     # Load an example survival data from CSV into a Dask data frame.

demo/dask/cpu_training.py

@@ -3,11 +3,11 @@ Example of training with Dask on CPU
 ====================================
 
 """
-import xgboost as xgb
-from xgboost.dask import DaskDMatrix
-from dask.distributed import Client
-from dask.distributed import LocalCluster
 from dask import array as da
+from dask.distributed import Client, LocalCluster
+from xgboost.dask import DaskDMatrix
+
+import xgboost as xgb
 
 
 def main(client):

demo/dask/dask_callbacks.py

@@ -3,12 +3,12 @@ Example of using callbacks with Dask
 ====================================
 """
 import numpy as np
-import xgboost as xgb
-from xgboost.dask import DaskDMatrix
-from dask.distributed import Client
-from dask.distributed import LocalCluster
+from dask.distributed import Client, LocalCluster
 from dask_ml.datasets import make_regression
 from dask_ml.model_selection import train_test_split
+from xgboost.dask import DaskDMatrix
+
+import xgboost as xgb
 
 
 def probability_for_going_backward(epoch):

demo/dask/gpu_training.py

@@ -2,14 +2,15 @@
 Example of training with Dask on GPU
 ====================================
 """
-from dask_cuda import LocalCUDACluster
 import dask_cudf
-from dask.distributed import Client
 from dask import array as da
 from dask import dataframe as dd
+from dask.distributed import Client
+from dask_cuda import LocalCUDACluster
+from xgboost.dask import DaskDMatrix
+
 import xgboost as xgb
 from xgboost import dask as dxgb
-from xgboost.dask import DaskDMatrix
 
 
 def using_dask_matrix(client: Client, X, y):

demo/dask/sklearn_cpu_training.py

@@ -2,9 +2,9 @@
 Use scikit-learn regressor interface with CPU histogram tree method
 ===================================================================
 """
-from dask.distributed import Client
-from dask.distributed import LocalCluster
 from dask import array as da
+from dask.distributed import Client, LocalCluster
+
 import xgboost
 
 

demo/dask/sklearn_gpu_training.py

@@ -3,10 +3,12 @@ Use scikit-learn regressor interface with GPU histogram tree method
 ===================================================================
 """
 
+from dask import array as da
 from dask.distributed import Client
+
 # It's recommended to use dask_cuda for GPU assignment
 from dask_cuda import LocalCUDACluster
-from dask import array as da
+
 import xgboost