Fix lazy import of optional packages

Author: AVHopp

baybe/utils/plotting.py

@@ -1,6 +1,9 @@
 """Plotting utilities."""
 
+import json
 import os
+import sys
+import warnings
 from pathlib import Path
 
 import pandas as pd
@@ -32,10 +35,7 @@ def create_example_plots(
     if "SMOKE_TEST" in os.environ:
         return
 
-    # Lazily import required packages
-    import json
-    import sys
-
+    # Lazily import optional packages which are now required
     import matplotlib.pyplot as plt
     import seaborn as sns
 
@@ -52,8 +52,6 @@ def create_example_plots(
         while not script_path.name == "baybe" and script_path != script_path.parent:
             script_path = script_path.parent
         if script_path == script_path.parent:
-            import warnings
-
             warnings.warn("No themes for plotting found. A default theme is used.")
             themes = {"check": {"font_scale": 1.75, "rc_params": {}}}
         else:
@@ -77,6 +75,4 @@ def create_example_plots(
             )
             plt.clf()
         else:
-            import warnings
-
             warnings.warn("No keyword arguments were provided when plotting.")