[pre-commit.ci] auto fixes from pre-commit.com hooks

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tests/tools/dumping/test_collection.py

@@ -11,13 +11,12 @@
 # TODO: Test that de-duplication also works for calculations
 # TODO: Test incremental dumping
 
-from datetime import datetime
 from pathlib import Path
 
 import pytest
 
 from aiida import orm
-from aiida.tools.dumping import CollectionDumper, collection
+from aiida.tools.dumping import CollectionDumper
 
 from .test_utils import compare_tree
 
@@ -84,9 +83,7 @@ def test_should_dump_processes(self, setup_no_process_group, setup_add_group):
 
         assert collection_dumper.should_dump_processes() is True
 
-
     def test_get_nodes_add_group(self, setup_add_group):
-
         add_group: orm.Group = setup_add_group
 
         collection_dumper = CollectionDumper(collection=add_group)
@@ -261,4 +258,4 @@ def test_dump_calculations(self, setup_add_group, setup_multiply_add_group, tmp_
 
     #     with pytest.raises(TypeError):
     #         collection_dumper = CollectionDumper(collection=[1])
-    #         collection_dumper._get_nodes()
+    #         collection_dumper._get_nodes()