Use symbol for degrees Celsius instead of coulombs

visualizer/data.py

@@ -13,7 +13,7 @@ from .records import get_link
 Measurement = make_dataclass('Measurement',
                              ['slug', 'field', 'title', 'units'])
 measurements = {m.slug: m for m in (
-    Measurement('temperature', 1, 'Temperature', 'C'),
+    Measurement('temperature', 1, 'Temperature', '\u00b0C'),
     Measurement('pressure', 2, 'Pressure', 'hPa'),
     Measurement('wind-speed', 3, 'Wind Speed', 'm/s'),
 )}