title: Can't get a simply Django app to build on Docker (Must have Postgres + Mysql support)
body: <p>Dockerfile:</p>
  
  <pre><code># pull official base image
  FROM alpine:edge
  
  RUN apk update &amp;&amp; apk add build-base libzmq musl-dev python3 python3-dev zeromq-dev \
                    mariadb-dev postgresql-dev
  
  RUN pip3 install pyzmq
  
  # set work directory
  WORKDIR /usr/src/myproj
  COPY ./requirements.txt ./requirements.txt
  # install dependencies
  RUN pip3 install --upgrade pip
  RUN pip3 install -r requirements.txt
  
  COPY . /usr/src/myproj
  
  
  # reduce image size by cleaning up the build packages
  RUN apk del build-base musl-dev python3-dev zeromq-dev
  
  
  EXPOSE 8000
  CMD ["python", "manage.py", "runserver", "0.0.0.0:8000"]
  </code></pre>
  
  <p>My requirements.txt</p>
  
  <pre><code>alive-progress==1.3.0
  amqp==2.5.1
  appnope==0.1.0
  APScheduler==3.5.3
  argh==0.26.2
  astroid==2.2.4
  attrs==19.1.0
  awsebcli==3.14.4
  Babel==2.6.0
  backcall==0.1.0
  billiard==3.6.1.0
  bleach==3.1.0
  blessed==1.15.0
  botocore==1.10.84
  bugsnag==3.6.0
  cached-property==1.4.3
  celery==4.3.0
  cement==2.8.2
  certifi==2018.8.24
  chardet==3.0.4
  colorama==0.3.9
  decorator==4.3.2
  defusedxml==0.5.0
  dj-database-url==0.5.0
  Django==2.2.4
  django-cors-headers==3.0.2
  django-enum-choices==2.1.1
  django-enumchoicefield==2.0.0
  django-extensions==2.2.1
  django-redis==4.10.0
  djangorestframework==3.9.4
  dnspython==1.16.0
  docker==3.5.0
  docker-compose==1.21.2
  docker-pycreds==0.3.0
  dockerpty==0.4.1
  docopt==0.6.2
  docutils==0.14
  entrypoints==0.3
  flower==0.9.2
  gunicorn==19.9.0
  html2text==2019.9.26
  idna==2.6
  importlib-metadata==0.19
  importlib-resources==1.0.2
  ipykernel==5.1.0
  ipython==7.3.0
  ipython-genutils==0.2.0
  ipywidgets==7.4.2
  isodate==0.6.0
  isort==4.3.10
  jedi==0.13.3
  Jinja2==2.10
  jmespath==0.9.3
  jsonfield==2.0.2
  jsonschema==2.6.0
  jupyter==1.0.0
  jupyter-client==5.2.4
  jupyter-console==6.0.0
  jupyter-core==4.4.0
  jwplatform==1.2.2
  kombu==4.6.4
  lazy-object-proxy==1.3.1
  MarkupSafe==1.1.1
  mccabe==0.6.1
  mistune==0.8.4
  more-itertools==7.2.0
  mysql-connector==2.2.9
  mysqlclient==1.4.6
  nbconvert==5.4.1
  nbformat==4.4.0
  notebook==5.7.5
  numpy==1.17.4
  pandocfilters==1.4.2
  parso==0.3.4
  pathspec==0.5.5
  pathtools==0.1.2
  pexpect==4.6.0
  pi==0.1.2
  pickleshare==0.7.5
  powerline-status==2.7
  prometheus-client==0.6.0
  prompt-toolkit==2.0.9
  protobuf==3.6.1
  psycopg2==2.7.5
  psycopg2-binary==2.7.5
  ptyprocess==0.6.0
  Pygments==2.3.1
  pylint==2.3.1
  PyMySQL==0.9.3
  pyrsistent==0.14.11
  python-dateutil==2.7.3
  python-slugify==3.0.3
  pytz==2018.5
  PyYAML==3.13
  pyzmq==18.0.1
  qtconsole==4.4.3
  redis==3.3.8
  requests==2.18.4
  requests-toolbelt==0.9.1
  semantic-version==2.5.0
  Send2Trash==1.5.0
  six==1.11.0
  sqlparse==0.3.0
  tabulate==0.7.5
  termcolor==1.1.0
  terminado==0.8.1
  testpath==0.4.2
  text-unidecode==1.2
  texttable==0.9.1
  timezonefinder==4.1.0
  tornado==5.1
  traitlets==4.3.2
  typed-ast==1.3.1
  tzlocal==1.5.1
  Unidecode==1.1.1
  urllib3==1.22
  uWSGI==2.0.17.1
  validators==0.14.0
  vine==1.3.0
  watchdog==0.9.0
  wcwidth==0.1.7
  webencodings==0.5.1
  WebOb==1.8.5
  websocket-client==0.51.0
  widgetsnbextension==3.4.2
  wrapt==1.11.1
  zerobouncesdk==0.0.6
  zipp==0.6.0
  </code></pre>
  
  <p>Running docker build produces this error:</p>
  
  <pre><code>ERROR: Command errored out with exit status 1:
       command: /usr/bin/python3.8 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-67emofjc/typed-ast/setup.py'"'"'; __file__='"'"'/tmp/pip-install-67emofjc/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-3om7rooa/install-record.txt --single-version-externally-managed --compile --install-headers /usr/include/python3.8/typed-ast
           cwd: /tmp/pip-install-67emofjc/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 -&gt; build/lib.linux-x86_64-3.8/typed_ast
      copying typed_ast/conversions.py -&gt; build/lib.linux-x86_64-3.8/typed_ast
      copying typed_ast/ast27.py -&gt; build/lib.linux-x86_64-3.8/typed_ast
      copying typed_ast/ast3.py -&gt; 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
      gcc -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Os -fomit-frame-pointer -g -Os -fomit-frame-pointer -g -Os -fomit-frame-pointer -g -DTHREAD_STACK_SIZE=0x100000 -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 'gcc' failed with exit status 1
      ----------------------------------------
  ERROR: Command errored out with exit status 1: /usr/bin/python3.8 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-67emofjc/typed-ast/setup.py'"'"'; __file__='"'"'/tmp/pip-install-67emofjc/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-3om7rooa/install-record.txt --single-version-externally-managed --compile --install-headers /usr/include/python3.8/typed-ast Check the logs for full command output.
  </code></pre>