Duplicate signal name: "selector080_Fiscal_Week"

I am trying to create a regression line using Altair and Streamlit and I am getting the following error while trying to execute the same: Duplicate signal name: “selector080_Fiscal_Week”

Below is the code I am using:

import streamlit as st
import pandas as pd
import numpy as np
import altair as alt

def scatter_chart(f, col1, col2):
    scatter = alt.Chart(f).mark_point().encode(
    x=col1,
    y=col2,
    tooltip=[col1, col2]).interactive()
    reg = scatter.transform_regression(col1,col2).mark_line()
    return scatter

st.altair_chart(scatter_chart(df, scatter_opt1, scatter_opt2), use_container_width = True)

Please let me know the issue and how to resolve it ?

[jakevdp]

OK, in that case the issue is that you are layering two charts with the same interaction signal, exactly as in my snippet above. The solution is to put the interaction in only one of the layers, like this:

import altair as alt
chart = alt.Chart('data.csv').mark_point()
chart + chart.interactive()

[anshulcool1989]

Thanks a lot for the help. Your solution worked.