Update ColumnChart example with improved annotations and data source

docs/user-guide/charts/column-charts.md

@@ -1,15 +1,15 @@
 # ColumnChart
 
-## Example
+This example, drawn from <a href="https://www.datawrapper.de/charts/column">the Datawrapper documentation</a>, demonstrates how to customize a column chart with annotations and custom colors.
 
-This example demonstrates how to create a column chart showing U.S. unemployment rates from 2016-2020, highlighting the dramatic spike during the COVID-19 pandemic.
+<iframe title="U.S. unemployment rate" aria-label="Column Chart" id="datawrapper-chart-smskc" src="https://datawrapper.dwcdn.net/smskc/1/" scrolling="no" frameborder="0" style="width: 0; min-width: 100% !important; border: none;" height="400" data-external="1"></iframe><script type="text/javascript">window.addEventListener("message",function(a){if(void 0!==a.data["datawrapper-height"]){var e=document.querySelectorAll("iframe");for(var t in a.data["datawrapper-height"])for(var r,i=0;r=e[i];i++)if(r.contentWindow===a.source){var d=a.data["datawrapper-height"][t]+"px";r.style.height=d}}});</script>
 
 ```python
 import pandas as pd
 import datawrapper as dw
 
 # Load unemployment data from GitHub
-url = "https://raw.githubusercontent.com/palewire/datawrapper-api-classes/main/tests/samples/column/unemployment.csv"
+url = "https://raw.githubusercontent.com/chekos/datawrapper/main/tests/samples/column/unemployment.csv"
 df = pd.read_csv(url)
 
 chart = dw.ColumnChart(
@@ -19,30 +19,53 @@ chart = dw.ColumnChart(
     source_name="U.S. Bureau of Labor Statistics",
     source_url="https://www.bls.gov/",
     # Introductory text
-    intro="Seasonally adjusted unemployment rate, January 2016 - September 2020",
-    # Chart byline
-    byline="Sergio Hernandez",
+    intro="January 2016-September 2020",
     # Data from pandas DataFrame
     data=df,
-    # Format Y-axis grid labels with one decimal place
-    y_grid_format=dw.NumberFormat.ONE_DECIMAL,
-    # Always show value labels
-    show_value_labels="always",
-    # Place value labels outside the columns
-    value_labels_placement="outside",
+    # Format Y-axis grid labels with one decimal place and a percentage sign
+    y_grid_format=dw.NumberFormat.PERCENT_UP_TO_ONE_DECIMAL,
     # Format value labels with one decimal place
-    value_labels_format=dw.NumberFormat.ONE_DECIMAL,
-    # Set fixed plot height in pixels
-    plot_height=228,
+    value_labels_format=dw.NumberFormat.PERCENT_UP_TO_ONE_DECIMAL,
     # Highlight specific column in red
-    column_color={"2020/04": "#c71e1d"},
+    base_color="#CCCCCC",
+    color_category={
+        "2020/04": "rgb(21, 96, 122)",
+        "2020/05": "rgb(21, 96, 122)",
+        "2020/06": "rgb(21, 96, 122)",
+        "2020/07": "rgb(21, 96, 122)",
+        "2020/08": "rgb(21, 96, 122)",
+        "2020/09": "rgb(21, 96, 122)",
+    },
+    range_annotations=[
+        dw.RangeAnnotation(
+            x0="2020/01/01",
+            x1="2020/09/30",
+            color="#777777",
+            opacity=10,
+            type="x",
+        )
+    ],
+    text_annotations=[
+        dw.TextAnnotation(
+            x="2020/04/01",
+            y=14,
+            dx=-50,
+            dy=50,
+            text="In <b>April 2020</b>, the unemployment rate rose to almost <b>15%</b>.",
+            align="tr",
+            size=14,
+            color="rgb(21, 96, 122)",
+            connector_line=dw.ConnectorLine(
+                color="rgb(21, 96, 122)",
+                type=dw.ConnectorLineType.CURVE_RIGHT,
+            ),
+        )
+    ],
 )
 
 chart.create()
 ```
 
-<div style="min-height:433px" id="datawrapper-vis-1rJm1"><script type="text/javascript" defer src="https://datawrapper.dwcdn.net/1rJm1/embed.js" charset="utf-8" data-target="#datawrapper-vis-1rJm1"></script><noscript><img src="https://datawrapper.dwcdn.net/1rJm1/full.png" alt="" /></noscript></div>
-
 ## Reference
 
 ```{eval-rst}