Rename the 'gender' coloring to be more freeform, and make it an optional field.

example.json

@@ -1,7 +1,7 @@
 { "members": [
     {"name": "Alice", "color": "pink"},
     {"name": "Bob", "color": "blue"},
-    {"name": "Sam", "color": "green"},
+    {"name": "Sam"},
     {"name": "Eve", "color": "pink"},
     {"name": "Charles", "color": "blue"},
     {"name": "Max", "color": "yellow"}

polygraph.py

@@ -8,7 +8,7 @@ def parse_args():
     parser = argparse.ArgumentParser(description='Generate graphs of polyamorous family networks from data files')
     parser.add_argument('--input', '-i', default='network.json', help='Input file in json format')
     parser.add_argument('--output', '-o', default='network.png', help='Output image file. Format auto-detected from file extension')
-    parser.add_argument('--gender', '-g', action='store_true', help='Include gender colors in output graph')
+    parser.add_argument('--color', '-c', action='store_true', help='Include node colors in output graph')
     return parser.parse_args()
 
 
@@ -28,11 +28,11 @@ def main():
 
     # Add nodes to graph
     for user in data['members']:
-        gender_color = 'white'
+        node_color = 'white'
-        if settings.gender:
+        if settings.color and user.has_key('color'):
-            gender_color = user['color']
+            node_color = user['color']
 
-        graph.add_node(user['name'], fillcolor=gender_color)
+        graph.add_node(user['name'], fillcolor=node_color)
 
     # Add edges to graph
     edge_style = 'solid'