Which song mentions two prime ministers?

In John Lennon famously imagined a world with 'no possessions'. In April 1966, The Beatles were informed by their accountants that such a day might be fast approaching. 

The new UK government had just introduced a 95% 'super tax' for the highest earners. This left the Fab Four in a precarious financial position. "Two of you are close to being bankrupt, and the other two could soon be."

Lyrical Tax Return

Shocked to realise "even though we had started earning money, we were actually giving most of it away in taxes," George Harrison responded in song. Taxman is one of his most biting lyrics, including a direct reference to the super tax

"There's one for you, nineteen for me."

In his final interview in 1980, John Lennon said that he reluctantly helped complete the lyric:

"I threw in a few one-liners to help the song along, because that's what he asked for."

Mr Wilson and Mr Heath

There is a shout-out to the (then) prime minister, Mr Wilson, in the backing vocals. This is followed by the same to Mr Heath, then the Leader of the Opposition and future prime minister (1970-74).

Don't ask me what I want it for

(Ah, ah, Mr. Wilson)

If you don't want to pay some more

(Ah, ah, Mr. Heath)

'Cause I'm the taxman

By naming both the leading politicians, the song avoided problems regarding radio play. Britain has strict rules about 'party political' broadcasting.