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diff --git a/aoc2023/build/packages/gleam_stdlib/src/gleam/pair.gleam b/aoc2023/build/packages/gleam_stdlib/src/gleam/pair.gleam
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+/// Returns the first element in a pair.
+///
+/// ## Examples
+///
+/// ```gleam
+/// > first(#(1, 2))
+/// 1
+/// ```
+///
+pub fn first(pair: #(a, b)) -> a {
+  let #(a, _) = pair
+  a
+}
+
+/// Returns the second element in a pair.
+///
+/// ## Examples
+///
+/// ```gleam
+/// > second(#(1, 2))
+/// 2
+/// ```
+///
+pub fn second(pair: #(a, b)) -> b {
+  let #(_, a) = pair
+  a
+}
+
+/// Returns a new pair with the elements swapped.
+///
+/// ## Examples
+///
+/// ```gleam
+/// > swap(#(1, 2))
+/// #(2, 1)
+/// ```
+///
+pub fn swap(pair: #(a, b)) -> #(b, a) {
+  let #(a, b) = pair
+  #(b, a)
+}
+
+/// Returns a new pair with the first element having had `with` applied to
+/// it.
+///
+/// ## Examples
+///
+/// ```gleam
+/// > #(1, 2) |> map_first(fn(n) { n * 2 })
+/// #(2, 2)
+/// ```
+///
+pub fn map_first(of pair: #(a, b), with fun: fn(a) -> c) -> #(c, b) {
+  let #(a, b) = pair
+  #(fun(a), b)
+}
+
+/// Returns a new pair with the second element having had `with` applied to
+/// it.
+///
+/// ## Examples
+///
+/// ```gleam
+/// > #(1, 2) |> map_second(fn(n) { n * 2 })
+/// #(1, 4)
+/// ```
+///
+pub fn map_second(of pair: #(a, b), with fun: fn(b) -> c) -> #(a, c) {
+  let #(a, b) = pair
+  #(a, fun(b))
+}
+
+/// Returns a new pair with the given elements. This can also be done using the dedicated
+/// syntax instead: `new(1, 2) == #(1, 2)`.
+/// 
+/// ## Examples
+/// 
+/// ```gleam
+/// > new(1, 2)
+/// #(1, 2)
+/// ```
+/// 
+pub fn new(first: a, second: b) -> #(a, b) {
+  #(first, second)
+}