fix docs with added lines in yml

.readthedocs.yml

@@ -1,6 +1,16 @@
 # Required
 version: 2
 
+# Set the OS, Python version and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.7"
+    # You can also specify other tool versions:
+    # nodejs: "20"
+    # rust: "1.70"
+    # golang: "1.20"
+
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
   builder: html

docs/python/tutorials/plot_tutorial_01_basics.py

@@ -16,7 +16,9 @@
 
 ###################################################################
 # Lets have a look at the cortical thickness data. To do this,
-# we will use the surface plotter included with BrainSpace.
+# we will use the surface plotter included with BrainSpace. As we'll
+# be plotting data onto these hemispheres quite often in this tutorial
+# we'll create a simple function for it and plot mean thickness here.
 import numpy as np
 from brainspace.plotting import plot_hemispheres