Use importlib.util.find_spec for modules that are not used (ruff F401)

pygmt/src/tilemap.py

@@ -1,17 +1,12 @@
 """
 tilemap - Plot XYZ tile maps.
 """
+import importlib
+
 from pygmt.clib import Session
 from pygmt.datasets.tile_map import load_tile_map
 from pygmt.helpers import build_arg_string, fmt_docstring, kwargs_to_strings, use_alias
 
-try:
-    import rioxarray
-
-    _has_rioxarray = True
-except ImportError:
-    _has_rioxarray = False
-
 
 @fmt_docstring
 @use_alias(
@@ -116,7 +111,7 @@ def tilemap(
     """
     kwargs = self._preprocess(**kwargs)  # pylint: disable=protected-access
 
-    if not _has_rioxarray:
+    if importlib.util.find_spec("rioxarray") is None:
         raise ImportError(
             "Package `rioxarray` is required to be installed to use this function. "
             "Please use `python -m pip install rioxarray` or "

pygmt/tests/test_figure.py

@@ -3,24 +3,19 @@
 
 Doesn't include the plotting commands which have their own test files.
 """
+import importlib
 import os
 from pathlib import Path
 
-try:
-    import IPython
-
-    _has_ipython = True
-except ImportError:
-    _has_ipython = False
-
-
 import numpy as np
 import numpy.testing as npt
 import pytest
 from pygmt import Figure, set_display
 from pygmt.exceptions import GMTError, GMTInvalidInput
 from pygmt.helpers import GMTTempFile
 
+HAS_IPYTHON = bool(importlib.util.find_spec("IPython"))
+
 
 def test_figure_region():
     """
@@ -315,7 +310,7 @@ def test_figure_savefig_worldfile():
                 fig.savefig(fname=imgfile.name, worldfile=True)
 
 
-@pytest.mark.skipif(not _has_ipython, reason="run when IPython is installed")
+@pytest.mark.skipif(not HAS_IPYTHON, reason="run when IPython is installed")
 def test_figure_show():
     """
     Test that show creates the correct file name and deletes the temp dir.
@@ -356,7 +351,7 @@ def test_figure_show_invalid_method():
         fig.show(method="test")
 
 
-@pytest.mark.skipif(_has_ipython, reason="run without IPython installed")
+@pytest.mark.skipif(HAS_IPYTHON, reason="run without IPython installed")
 def test_figure_show_notebook_error_without_ipython():
     """
     Test to check if an error is raised when display method is 'notebook', but