Implement StmtReturn (#4960)

* Implement StmtPass

This implements StmtPass as `pass`.

The snapshot diff is small because pass mainly occurs in bodies and function (#4951) and if/for bodies.

* Implement StmtReturn

This implements StmtReturn as `return` or `return {value}`.

The snapshot diff is small because return occurs in functions (#4951)

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__power_op_spacing_py.snap

@@ -178,7 +178,7 @@ return np.divide(
 -return np.divide(
 -    where=view.sum_of_weights_of_weight_long**2 > view.sum_of_weights_squared,  # type: ignore
 -)
-+NOT_YET_IMPLEMENTED_StmtReturn
++return NOT_IMPLEMENTED_call()
 ```
 
 ## Ruff Output
@@ -234,7 +234,7 @@ q = [i for i in []]
 # WE SHOULD DEFINITELY NOT EAT THESE COMMENTS (https://github.com/psf/black/issues/2873)
 NOT_YET_IMPLEMENTED_StmtIf
 
-NOT_YET_IMPLEMENTED_StmtReturn
+return NOT_IMPLEMENTED_call()
 ```
 
 ## Black Output

crates/ruff_python_formatter/src/statement/stmt_return.rs

@@ -1,5 +1,7 @@
-use crate::{not_yet_implemented, FormatNodeRule, PyFormatter};
+use crate::expression::parentheses::Parenthesize;
-use ruff_formatter::{write, Buffer, FormatResult};
+use crate::{AsFormat, FormatNodeRule, PyFormatter};
+use ruff_formatter::prelude::{space, text};
+use ruff_formatter::{write, Buffer, Format, FormatResult};
 use rustpython_parser::ast::StmtReturn;
 
 #[derive(Default)]
@@ -7,6 +9,18 @@ pub struct FormatStmtReturn;
 
 impl FormatNodeRule<StmtReturn> for FormatStmtReturn {
     fn fmt_fields(&self, item: &StmtReturn, f: &mut PyFormatter) -> FormatResult<()> {
-        write!(f, [not_yet_implemented(item)])
+        let StmtReturn { range: _, value } = item;
+        if let Some(value) = value {
+            write!(
+                f,
+                [
+                    text("return"),
+                    space(),
+                    value.format().with_options(Parenthesize::IfBreaks)
+                ]
+            )
+        } else {
+            text("return").fmt(f)
+        }
     }
 }