How is “sink or swim” used?

In Water for Elephants (2011), one line is: “Let's get up there! It's sink or swim around here.”

Which movie is “sink or swim” from?

The clip at the top of this page is from Water for Elephants (2011).

Idiom

to be in a situation where you will either succeed by your own efforts or fail completely

Heard in 4 movies

to be in a situation where you will either succeed by your own efforts or fail completely
The new students were just left to sink or swim.

Definitions from the Oxford Advanced Learner's Dictionary, 9th edition

Let's get up there! It's sink or swim around here.

Said in 4 films · #1