package typed-ast older versions doesn't work on python 3.8?

Hi, Ethan ✌ I just set PythonBuddy in my WSL installation and during the installation of the required packages an error was raised. I was able to fix it so I’m posting the step here in case anyone is interested.

Steps to reproduce the behavior:

1. Ubuntu 20.04 on Windows Subsystem for Linux
2. Python 3.8
3. Clone the repo, create a virtualenv for it
4. Try to install the required packages and get the following error:

    Running setup.py install for typed-ast ... error
    ERROR: Command errored out with exit status 1:
     command: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-tr7ufsax/typed-ast/setup.py'"'"'; __file__='"'"'/tmp/pip-install-tr7ufsax/typed-ast/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-qwpgruzh/install-record.txt --single-version-externally-managed --user --prefix= --compile --install-headers /home/marcelo/.local/include/python3.8/typed-ast
         cwd: /tmp/pip-install-tr7ufsax/typed-ast/
    Complete output (23 lines):
    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-x86_64-3.8
    creating build/lib.linux-x86_64-3.8/typed_ast
    copying typed_ast/__init__.py -> build/lib.linux-x86_64-3.8/typed_ast
    copying typed_ast/ast27.py -> build/lib.linux-x86_64-3.8/typed_ast
    copying typed_ast/ast3.py -> build/lib.linux-x86_64-3.8/typed_ast
    copying typed_ast/conversions.py -> build/lib.linux-x86_64-3.8/typed_ast
    running build_ext
    building '_ast27' extension
    creating build/temp.linux-x86_64-3.8
    creating build/temp.linux-x86_64-3.8/ast27
    creating build/temp.linux-x86_64-3.8/ast27/Parser
    creating build/temp.linux-x86_64-3.8/ast27/Python
    creating build/temp.linux-x86_64-3.8/ast27/Custom
    x86_64-linux-gnu-gcc -pthread -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O2 -Wall -g -fstack-protector-strong -Wformat -Werror=format-security -g -fwrapv -O2 -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -Iast27/Include -I/usr/include/python3.8 -c ast27/Parser/acceler.c -o build/temp.linux-x86_64-3.8/ast27/Parser/acceler.o
    ast27/Parser/acceler.c:13:10: fatal error: pgenheaders.h: No such file or directory
       13 | #include "pgenheaders.h"
          |          ^~~~~~~~~~~~~~~
    compilation terminated.
    error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

Expected behavior ´´pip3 install -r should execute without errors´´

I managed to fix this by upgrading the version of the package that is being accused of raising the error. Someone at Stackoverflow had a similar issue and the solution worked for me here too. Solution:

Upgrading to typed-ast==1.4.1 worked for me using Python 3.8.5

After the solution was applied I could install the required packages without errors.