Suppose i have the data frame below:

I checked the documentation but it's only based on a single column.
Reproducible code:
x = np.random.normal(100,5,100)
data = pd.DataFrame(x)
epsilon = 10
data.columns = ['x']
data['lower'] = x - epsilon
data['upper'] = x + epsilon
data
I'd actually like to use altair, since i like it's interactivity.
