mesclar duas colunas pandas
df["period"] = df["Year"] + df["quarter"]
Tremendous Enceladus
df["period"] = df["Year"] + df["quarter"]
df = df['Day'].map(str) + '-' + df['Month'].map(str) + '-' + df['Year'].map(str)
df1 = df['1st Column Name'].map(str) + df['2nd Column Name'].map(str) + ...