Coding st.session_state inside st.sidebar

Using Streamlit
1

Hi! How do you put this code in a st.sidebar? I got it from another thread and found it better suited for my purpose. When you write with sidebar(): before it an error occurs. I think this st.columns comes out, doesn’t it?

def changevalue(category):
    st.session_state.df = st.session_state.df[st.session_state.df[category]==st.session_state[category]]
    
cols = st.columns[4]
product = cols[0].st.selectbox("PRODUCT", st.session_state.df.Product.unique(), key="Product", on_change=changevalue, kwargs={'category': "Product"})
region  = cols[1].st.selectbox("REGION", st.session_state.df.Region.unique(), key="Region" , on_change=changevalue, kwargs={'category': "Region"})
state = cols[2].st.selectbox("STATE", st.session_state.df.State.unique(), key="State" , on_change=changevalue, kwargs={'category': "State"})
city = cols[3].st.selectbox("CITY", st.session_state.df.City.unique(), key="City", on_change=changevalue, kwargs={'category': "City"})

if 'df' not in st.session_state or st.button("RESET FILTER"):
    st.session_state.df = df

st.dataframe(st.session_state.df)