English
The source of the identity partial equivalence on a set s is s.
Русский
Источник тождественной частичной эквивалентности на множестве s равен s.
LaTeX
$$$\\text{ofSet}_\\text{source}(s) = s$$$
Lean4
/-- The identity partial equivalence on a set `s` -/
def ofSet (s : Set α) : PartialEquiv α α where
toFun := id
invFun := id
source := s
target := s
map_source' _ hx := hx
map_target' _ hx := hx
left_inv' _ _ := rfl
right_inv' _ _ := rfl