diff --git a/.circleci/create_conda_optional_env.sh b/.circleci/create_conda_optional_env.sh
index ebd907688a5..d1d48f7e998 100755
--- a/.circleci/create_conda_optional_env.sh
+++ b/.circleci/create_conda_optional_env.sh
@@ -14,7 +14,7 @@ if [ ! -d $HOME/miniconda/envs/circle_optional ]; then
     ./miniconda.sh -b -p $HOME/miniconda
 
     # Create environment
-    # PYTHON_VERSION=3.6
+    # PYTHON_VERSION=2.7 or 3.5
     $HOME/miniconda/bin/conda create -n circle_optional --yes python=$PYTHON_VERSION \
 requests nbformat six retrying psutil pandas decorator pytest mock nose poppler xarray scikit-image ipython jupyter ipykernel ipywidgets
 
diff --git a/doc/python/marker-style.md b/doc/python/marker-style.md
index e456d7f41f9..865ff1052f1 100644
--- a/doc/python/marker-style.md
+++ b/doc/python/marker-style.md
@@ -5,8 +5,8 @@ jupyter:
     text_representation:
       extension: .md
       format_name: markdown
-      format_version: "1.1"
-      jupytext_version: 1.1.7
+      format_version: '1.2'
+      jupytext_version: 1.3.2
   kernelspec:
     display_name: Python 3
     language: python
@@ -20,7 +20,7 @@ jupyter:
     name: python
     nbconvert_exporter: python
     pygments_lexer: ipython3
-    version: 3.6.5
+    version: 3.7.0
   plotly:
     description: How to style markers in Python with Plotly.
     display_as: file_settings
@@ -305,6 +305,125 @@ fig.show()
 
 ```
 
+### Custom Marker Symbols
+
+The `marker_symbol` attribute allows you to choose from a wide array of symbols to represent markers in your figures.
+
+The basic symbols are: `circle`, `square`, `diamond`, `cross`, `x`, `triangle`, `pentagon`, `hexagram`, `star`, `diamond`, `hourglass`, `bowtie`, `asterisk`, `hash`, `y`, and `line`. 
+
+Each basic symbol is also represented by a number. Adding 100 to that number is equivalent to appending the suffix "-open" to a symbol name. Adding 200 is equivalent to appending "-dot" to a symbol name. Adding 300 is equivalent to appending "-open-dot" or "dot-open" to a symbol name.
+
+In the following figures, hover over a symbol to see its name or number. Set the `marker_symbol` attribute equal to that name or number to change the marker symbol in your figure.
+
+#### Basic Symbols
+
+```python
+import plotly.graph_objects as go
+
+fig = go.Figure()
+
+fig.update_layout(title="Basic Symbols")
+
+fig.update_xaxes(showticklabels=False)
+fig.update_yaxes(showticklabels=False)
+
+for index in range(27):
+    fig.add_trace(go.Scatter(x=[(index % 6)], y=[index // 6],  name="",
+                             marker_symbol=index, marker_color='black', 
+                             marker_size=10, showlegend=False, mode="markers+text",
+                             textposition="middle right", text=f'<b>{index}</b>',
+                             hovertemplate=f'<b>Symbol Number: {index}</b>'))
+
+fig.show()    
+```
+
+#### All Symbols
+
+```python
+import plotly.graph_objects as go
+
+symbols = [0, 'circle', 100, 'circle-open', 200, 'circle-dot', 300,
+            'circle-open-dot', 1, 'square', 101, 'square-open', 201,
+            'square-dot', 301, 'square-open-dot', 2, 'diamond', 102,
+            'diamond-open', 202, 'diamond-dot', 302,
+            'diamond-open-dot', 3, 'cross', 103, 'cross-open', 203,
+            'cross-dot', 303, 'cross-open-dot', 4, 'x', 104, 'x-open',
+            204, 'x-dot', 304, 'x-open-dot', 5, 'triangle-up', 105,
+            'triangle-up-open', 205, 'triangle-up-dot', 305,
+            'triangle-up-open-dot', 6, 'triangle-down', 106,
+            'triangle-down-open', 206, 'triangle-down-dot', 306,
+            'triangle-down-open-dot', 7, 'triangle-left', 107,
+            'triangle-left-open', 207, 'triangle-left-dot', 307,
+            'triangle-left-open-dot', 8, 'triangle-right', 108,
+            'triangle-right-open', 208, 'triangle-right-dot', 308,
+            'triangle-right-open-dot', 9, 'triangle-ne', 109,
+            'triangle-ne-open', 209, 'triangle-ne-dot', 309,
+            'triangle-ne-open-dot', 10, 'triangle-se', 110,
+            'triangle-se-open', 210, 'triangle-se-dot', 310,
+            'triangle-se-open-dot', 11, 'triangle-sw', 111,
+            'triangle-sw-open', 211, 'triangle-sw-dot', 311,
+            'triangle-sw-open-dot', 12, 'triangle-nw', 112,
+            'triangle-nw-open', 212, 'triangle-nw-dot', 312,
+            'triangle-nw-open-dot', 13, 'pentagon', 113,
+            'pentagon-open', 213, 'pentagon-dot', 313,
+            'pentagon-open-dot', 14, 'hexagon', 114, 'hexagon-open',
+            214, 'hexagon-dot', 314, 'hexagon-open-dot', 15,
+            'hexagon2', 115, 'hexagon2-open', 215, 'hexagon2-dot',
+            315, 'hexagon2-open-dot', 16, 'octagon', 116,
+            'octagon-open', 216, 'octagon-dot', 316,
+            'octagon-open-dot', 17, 'star', 117, 'star-open', 217,
+            'star-dot', 317, 'star-open-dot', 18, 'hexagram', 118,
+            'hexagram-open', 218, 'hexagram-dot', 318,
+            'hexagram-open-dot', 19, 'star-triangle-up', 119,
+            'star-triangle-up-open', 219, 'star-triangle-up-dot', 319,
+            'star-triangle-up-open-dot', 20, 'star-triangle-down',
+            120, 'star-triangle-down-open', 220,
+            'star-triangle-down-dot', 320,
+            'star-triangle-down-open-dot', 21, 'star-square', 121,
+            'star-square-open', 221, 'star-square-dot', 321,
+            'star-square-open-dot', 22, 'star-diamond', 122,
+            'star-diamond-open', 222, 'star-diamond-dot', 322,
+            'star-diamond-open-dot', 23, 'diamond-tall', 123,
+            'diamond-tall-open', 223, 'diamond-tall-dot', 323,
+            'diamond-tall-open-dot', 24, 'diamond-wide', 124,
+            'diamond-wide-open', 224, 'diamond-wide-dot', 324,
+            'diamond-wide-open-dot', 25, 'hourglass', 125,
+            'hourglass-open', 26, 'bowtie', 126, 'bowtie-open', 27,
+            'circle-cross', 127, 'circle-cross-open', 28, 'circle-x',
+            128, 'circle-x-open', 29, 'square-cross', 129,
+            'square-cross-open', 30, 'square-x', 130, 'square-x-open',
+            31, 'diamond-cross', 131, 'diamond-cross-open', 32,
+            'diamond-x', 132, 'diamond-x-open', 33, 'cross-thin', 133,
+            'cross-thin-open', 34, 'x-thin', 134, 'x-thin-open', 35,
+            'asterisk', 135, 'asterisk-open', 36, 'hash', 136,
+            'hash-open', 236, 'hash-dot', 336, 'hash-open-dot', 37,
+            'y-up', 137, 'y-up-open', 38, 'y-down', 138,
+            'y-down-open', 39, 'y-left', 139, 'y-left-open', 40,
+            'y-right', 140, 'y-right-open', 41, 'line-ew', 141,
+            'line-ew-open', 42, 'line-ns', 142, 'line-ns-open', 43,
+            'line-ne', 143, 'line-ne-open', 44, 'line-nw', 144,
+            'line-nw-open']
+
+fig = go.Figure()
+
+fig.update_layout(title="Custom Marker Symbols", height=800)
+
+fig.update_xaxes(showticklabels=False)
+fig.update_yaxes(showticklabels=False)
+
+for index, symbol in enumerate(symbols[::2]): 
+    fig.add_trace(go.Scatter(x=[(index % 16)], y=[(index // 16)], 
+                                 marker_symbol=symbol, marker_color=index,
+                                 marker_size=20, showlegend=False, mode="markers+text",
+                                 name='',
+                                 hovertemplate=f'<b>Symbol Name: {symbols[2*index + 1]}</b><br><b>Symbol Number: {symbols[2*index]}</b>',
+                                 textfont_size=8
+                                ))
+  
+fig.show()
+```
+
+
 ### Reference
 
 See https://plot.ly/python/reference/ for more information and chart attribute options!