Update arrow_guide.py

Author: smartlixx

examples/shapes_and_collections/arrow_guide.py

@@ -9,7 +9,7 @@
 that behave differently when the data limits on a plot are changed. In general,
 points on a plot can either be fixed in "data space" or "display space".
 Something plotted in data space moves when the data limits are altered - an
-example would the points in a scatter plot. Something plotted in display space
+example would be the points in a scatter plot. Something plotted in display space
 stays static when data limits are altered - an example would be a figure title
 or the axis labels.