How to create a new column using data from 2 other columns in a dataframe

Question

I have a dataframe:

gp_df = CCA3            Country/Territory  year       GDP_USD
2662   AFG                  Afghanistan  1970  1.748887e+09
2661   AFE  Africa Eastern and Southern  1970  4.486261e+10
2663   AFW   Africa Western and Central  1970  2.350461e+10
2665   ALB                      Albania  1970           NaN
2720   DZA                      Algeria  1970  4.863487e+09
...    ...                          ...   ...           ...
16156  PSE           West Bank and Gaza  2020  1.553170e+10
16219  WLD                        World  2020  8.490680e+13
16222  YEM                  Yemen, Rep.  2020  1.884051e+10
16224  ZMB                       Zambia  2020  1.811063e+10
16225  ZWE                     Zimbabwe  2020  1.805117e+10

I want to create 2 new columns called '1970 gdp' and '2020 gdp' where it takes the 'GDP_USD' value at each year and matches it with the 'country/territory'

Example:

gp_df = CCA3    Country/Territory          1970 GDP        2020 GDP
2662   AFG                  Afghanistan    1.748887e+09    3.486261e+10
2661   AFE  Africa Eastern and Southern    4.486261e+10    7.345261e+10

This is what I've tried so far but it didn't work:

gp_df['1970 GDP'] = np.where(gp_df['year']
                       == '1970', year_GDP_USD.loc[gp_df.index], 0 )
gp_df['2020 GDP'] = np.where(gp_df['year']
                       == '2020', 'GDP_USD', 0 )