Compare 2 csv with python and add a new Column

I need to compare two csv files and add a new column on df_g with the Price column of df. I suppose I need to read line for line of the 2 csv but I don't know how I can do it so I try with it:

df = pd.read_csv('test2.csv')
df_g = pd.read_csv('test_hecho.csv')
if (df_g['Sitio'] == df['Sitio'] and df_g['Country'] == df['Country']):
    df_g['Bidfloor'] = df['Price']
df_g.to_csv('aaa.csv')

A possible answer is: df_g['Bidfloor'] = df_g[['Sitio','Country']].merge(df,how='left').Pricebut I need to change the =to = or part of. Is it possible??