diff --git a/properties/test_encode_decode.py b/properties/test_encode_decode.py
index 221083e16a1..4b0643cb2fe 100644
--- a/properties/test_encode_decode.py
+++ b/properties/test_encode_decode.py
@@ -4,9 +4,10 @@
 These ones pass, just as you'd hope!
 
 """
-import pytest  # isort:skip
+import pytest
 
 pytest.importorskip("hypothesis")
+# isort: split
 
 import hypothesis.extra.numpy as npst
 import hypothesis.strategies as st
diff --git a/setup.cfg b/setup.cfg
index c44d207bf0f..2059d471e23 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -161,7 +161,7 @@ exclude=
 [isort]
 profile = black
 skip_gitignore = true
-force_to_top = true
+float_to_top = true
 default_section = THIRDPARTY
 known_first_party = xarray
 
diff --git a/xarray/core/parallel.py b/xarray/core/parallel.py
index 2c7f4249b5e..20ec3608ebb 100644
--- a/xarray/core/parallel.py
+++ b/xarray/core/parallel.py
@@ -1,12 +1,3 @@
-try:
-    import dask
-    import dask.array
-    from dask.array.utils import meta_from_array
-    from dask.highlevelgraph import HighLevelGraph
-
-except ImportError:
-    pass
-
 import collections
 import itertools
 import operator
@@ -31,6 +22,16 @@
 from .dataarray import DataArray
 from .dataset import Dataset
 
+try:
+    import dask
+    import dask.array
+    from dask.array.utils import meta_from_array
+    from dask.highlevelgraph import HighLevelGraph
+
+except ImportError:
+    pass
+
+
 T_DSorDA = TypeVar("T_DSorDA", DataArray, Dataset)
 
 
diff --git a/xarray/tests/test_units.py b/xarray/tests/test_units.py
index 2140047f38e..543100ef98c 100644
--- a/xarray/tests/test_units.py
+++ b/xarray/tests/test_units.py
@@ -5,11 +5,6 @@
 import pandas as pd
 import pytest
 
-try:
-    import matplotlib.pyplot as plt
-except ImportError:
-    pass
-
 import xarray as xr
 from xarray.core import dtypes, duck_array_ops
 
@@ -23,6 +18,12 @@
 from .test_plot import PlotTestCase
 from .test_variable import _PAD_XR_NP_ARGS
 
+try:
+    import matplotlib.pyplot as plt
+except ImportError:
+    pass
+
+
 pint = pytest.importorskip("pint")
 DimensionalityError = pint.errors.DimensionalityError