Add Plot

Here is the `plot_graph()` that is in char of the bars, scatter and vertical line plot items.

Also all the necessary code  for the graph to be shown.

examples/max_pain.py

@@ -99,6 +99,8 @@ async def max_pain_daemon(
         """Update the bar graph with new open interest data."""
         plot.clear()
 
+        intrinsic_values = get_total_intrinsic_values(oi_by_strikes)
+
         for strike_str in sorted(oi_by_strikes, key=lambda x: int(x)):
             strike = int(strike_str)
             calls_val = float(oi_by_strikes[strike_str]['C'])
@@ -122,8 +124,6 @@ async def max_pain_daemon(
             )
             plot.addItem(bar_p)
 
-        for strike_str in sorted(intrinsic_values, key=lambda x: int(x)):
-            strike = int(strike_str)
             total_val = float(intrinsic_values[strike_str]['total']) / 100000
 
             scatter_iv = ScatterPlotItem(
@@ -136,7 +136,7 @@ async def max_pain_daemon(
             )
             plot.addItem(scatter_iv)
 
-        total_intrinsic_value, max_pain = get_intrinsic_value_and_max_pain(intrinsic_values)
+        _, max_pain = get_intrinsic_value_and_max_pain(intrinsic_values)
 
         vertical_line = InfiniteLine(
             pos=max_pain,