Add 3.13 support

DOCS.md

@@ -315,6 +315,7 @@ If the version of Python that the compiled code will be running on is known ahea
 - `3.10`: will work on any Python `>= 3.10`
 - `3.11`: will work on any Python `>= 3.11`
 - `3.12`: will work on any Python `>= 3.12`
+- `3.13`: will work on any Python `>= 3.12`
 - `sys`: chooses the target corresponding to the current Python version
 - `psf`: chooses the target corresponding to the oldest Python version not considered [end-of-life](https://devguide.python.org/versions/) by the PSF (Python Software Foundation)
 
@@ -1850,7 +1851,7 @@ Since Coconut syntax is a superset of Python 3 syntax, it supports [Python 3 fun
 
 Since not all supported Python versions support the [`typing`](https://docs.python.org/3/library/typing.html) module, Coconut provides the [`TYPE_CHECKING`](#type_checking) built-in for hiding your `typing` imports and `TypeVar` definitions from being executed at runtime. Coconut will also automatically use [`typing_extensions`](https://pypi.org/project/typing-extensions/) over `typing` objects at runtime when importing them from `typing`, even when they aren't natively supported on the current Python version (this works even if you just do `import typing` and then `typing.<Object>`).
 
-Furthermore, when compiling type annotations to Python 3 versions without [PEP 563](https://www.python.org/dev/peps/pep-0563/) support, Coconut wraps annotation in strings to prevent them from being evaluated at runtime (note that `--no-wrap-types` disables all wrapping, including via PEP 563 support).
+Furthermore, when compiling type annotations to Python 3 versions without [PEP 563](https://www.python.org/dev/peps/pep-0563/) support, Coconut wraps annotation in strings to prevent them from being evaluated at runtime (to avoid this, e.g. if you want to use annotations at runtime, `--no-wrap-types` will disable all wrapping, including via PEP 563 support). Only on Python 3.13+ does `--no-wrap-types` do nothing, since there [PEP 649](https://peps.python.org/pep-0649/) support is used instead.
 
 Additionally, Coconut adds special syntax for making type annotations easier and simpler to write. When inside of a type annotation, Coconut treats certain syntax constructs differently, compiling them to type annotations instead of what they would normally represent. Specifically, Coconut applies the following transformations:
 ```coconut

coconut/compiler/header.py

@@ -832,9 +832,11 @@ def getheader(which, use_hash, target, no_tco, strict, no_wrap):
 
     if not target.startswith("3"):
         header += "from __future__ import print_function, absolute_import, unicode_literals, division\n"
-    # including generator_stop here is fine, even though to universalize
-    #  generator returns we raise StopIteration errors, since we only do so
-    #  when target_info < (3, 3)
+    # including generator_stop here is fine, even though to universalize generator returns
+    #  we raise StopIteration errors, since we only do so when target_info < (3, 3)
+    elif target_info >= (3, 13):
+        # 3.13 supports lazy annotations, so we should just use that instead of from __future__ import annotations
+        header += "from __future__ import generator_stop\n"
     elif target_info >= (3, 7):
         if no_wrap:
             header += "from __future__ import generator_stop\n"

coconut/constants.py

@@ -182,15 +182,18 @@ def get_bool_env_var(env_var, default=False):
     (3, 10),
     (3, 11),
     (3, 12),
+    (3, 13),
 )
 
 py_vers_with_eols = (
     # must be in ascending order and kept up-to-date with https://devguide.python.org/versions
+    # (target, eol date)
     ("38", dt.datetime(2024, 11, 1)),
     ("39", dt.datetime(2025, 11, 1)),
     ("310", dt.datetime(2026, 11, 1)),
     ("311", dt.datetime(2027, 11, 1)),
     ("312", dt.datetime(2028, 11, 1)),
+    ("313", dt.datetime(2028, 11, 1)),
 )
 
 # must match supported vers above and must be replicated in DOCS
@@ -208,6 +211,7 @@ def get_bool_env_var(env_var, default=False):
     "310",
     "311",
     "312",
+    "313",
 )
 pseudo_targets = {
     "universal": "",