import "testing" func TestMyFunction(t *testing.T) { result := MyFunction(5) if result != 10 { t.Errorf("MyFunction(5) = %d; Expected 10", result) t.B.Fail() } }In this example, if the "result" of "MyFunction(5)" is not equal to 10, then the test would fail and the "t.B.Fail()" function would be called. The "t.Errorf()" function is used to print an error message indicating the specific test failure. The package library for this function is the built-in "testing" package in Go.