fix marker style doc

Author: nicolaskruchten

Diff for: doc/python/marker-style.md

@@ -6,7 +6,7 @@ jupyter:
       extension: .md
       format_name: markdown
       format_version: '1.2'
-      jupytext_version: 1.3.2
+      jupytext_version: 1.4.2
   kernelspec:
     display_name: Python 3
     language: python
@@ -20,7 +20,7 @@ jupyter:
     name: python
     nbconvert_exporter: python
     pygments_lexer: ipython3
-    version: 3.7.0
+    version: 3.7.7
   plotly:
     description: How to style markers in Python with Plotly.
     display_as: file_settings
@@ -323,8 +323,8 @@ raw_symbols = SymbolValidator().values
 namestems = []
 namevariants = []
 symbols = []
-for i in range(0,len(raw_symbols),2):
-    name = raw_symbols[i+1]
+for i in range(0,len(raw_symbols),3):
+    name = raw_symbols[i+2]
     symbols.append(raw_symbols[i])
     namestems.append(name.replace("-open", "").replace("-dot", ""))
     namevariants.append(name[len(namestems[-1]):])
@@ -335,11 +335,11 @@ fig = go.Figure(go.Scatter(mode="markers", x=namevariants, y=namestems, marker_s
                            hovertemplate="name: %{y}%{x}<br>number: %{marker.symbol}<extra></extra>"))
 fig.update_layout(title="Mouse over symbols for name & number!",
                   xaxis_range=[-1,4], yaxis_range=[len(set(namestems)),-1], 
-                  margin=dict(b=0,r=0), xaxis_side="top", height=1200, width=400)
+                  margin=dict(b=0,r=0), xaxis_side="top", height=1400, width=400)
 fig.show()
 ```
 
 
 ### Reference
 
-See https://plotly.com/python/reference/ for more information and chart attribute options!
+See https://plotly.com/python/reference/ for more information and chart attribute options!