Access Value Interactive type

I want to first filter an interactive dataframe by widget an then pass the result as a variable in a line plot. The result has the type “Interactive”, so it doesn’t work. Is there a way to access the value an pass it to the plot?

Category = pn.widgets.Select(name='Kennzahl', options=['Kennzahl1',
 'Kennzahl3 '])
mean = df[Category].mean()

plot = df.hvplot(x=x, y=mean, kind=‘line’)