Fail update ffi.h: No such file or directory

Hello, I’m trying to update from 0.72 to actual 0.85.

doing this is as the doc not working
I have this error

Building wheels for collected packages: bcrypt, cryptography, cffi
  Running setup.py bdist_wheel for bcrypt ... error
  Complete output from command /srv/homeassistant/bin/python3 -u -c "import setuptools, tokenize;__file__='/tmp/pip-install-3ncv_wqf/bcrypt/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /tmp/pip-wheel-jvxgrqrr --python-tag cp35:
  c/_cffi_backend.c:15:17: fatal error: ffi.h: No such file or directory
   #include <ffi.h>

tried to update wheel:

pip3 install --upgrade wheel

tried to update spip:

pip install --upgrade pip

same error
seems to miss something but do not know what

any idea?

Searching the forum reveals this answer

molobrakos

Dec '16

@keithh666, sudo apt-get install libffi-dev might help you out (without knowing much else about your setup).