Part A
G|-----------------------------|
D|----------5---5-3-5----------|
A|------5----------------------|
E|--3--------------------------|
[ Tab from: https://www.guitartabs.cc/tabs/g/gorillaz/19_2000_btab_ver_2.html ]
Part B
G|-----------------------------|
D|----------7---7-3-7----------|
A|------7----------------------|
E|--5--------------------------|
very simple bass line, the order jus goes: A(x2), B(x1), A(1x)
just repeat that for the whole song, theres a pause before "get the cool shoeshine" part