Fixed typo

salindersidhu · salindersidhu · commit 9a2def6be444 · 2018-03-08T14:37:56.000-05:00
diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -568,7 +568,7 @@ def validate_markevery(s):
                 raise ValueError("'markevery' tuple with first element of "
                                  "type float must have all elements of type "
                                  "float")
-            if not instance(tupType, (float, int)):
+            if not isinstance(tupType, (float, int)):
                 raise TypeError("'markevery' tuple is of an invalid type")
         if isinstance(s, list):
             if not all(isinstance(e, int) for e in s):
