Use literal syntax instead of function calls to create the data structure

doc/whats-new.rst

@@ -142,9 +142,7 @@ Internal Changes
 - Use ``async`` / ``await`` for the asynchronous distributed
   tests. (:issue:`3987`, :pull:`3989`)
   By `Justus Magin <https://github.com/keewis>`_.
-- Remove unnecessary comprehensions becuase the built-in functions like
-  ``all``, ``any``, ``enumerate``, ``sum``, ``tuple`` etc. can work directly with a
-  generator expression. (:pull:`4026`)
+- Various internal code clean-ups (:pull:`4026`,  :pull:`4038`).
   By `Prajjwal Nijhara <https://github.com/pnijhara>`_.
 
 .. _whats-new.0.15.1:

xarray/core/merge.py

@@ -841,7 +841,7 @@ def merge(
     from .dataarray import DataArray
     from .dataset import Dataset
 
-    dict_like_objects = list()
+    dict_like_objects = []
     for obj in objects:
         if not isinstance(obj, (DataArray, Dataset, dict)):
             raise TypeError(

xarray/util/print_versions.py

@@ -129,7 +129,7 @@ def show_versions(file=sys.stdout):
         ("sphinx", lambda mod: mod.__version__),
     ]
 
-    deps_blob = list()
+    deps_blob = []
     for (modname, ver_f) in deps:
         try:
             if modname in sys.modules: