update textbox param

Author: aitikgupta

lib/matplotlib/widgets.py

@@ -1018,10 +1018,12 @@ def __init__(self, ax, label, initial='',
         self.label = ax.text(
             -label_pad, 0.5, label, transform=ax.transAxes,
             verticalalignment='center', horizontalalignment='right')
+
+        # TextBox's text object should not parse mathtext at all.
         self.text_disp = self.ax.text(
             self.DIST_FROM_LEFT, 0.5, initial,
             transform=self.ax.transAxes, verticalalignment='center',
-            horizontalalignment='left', override_math=True)
+            horizontalalignment='left', parse_math=False)
 
         self._observers = cbook.CallbackRegistry()