Those packages are needed to build the cffi and cryptography wheels.
Without them, the following errors are thrown:
c/_cffi_backend.c:15:17: fatal error: ffi.h: No such file or directory
#include <ffi.h>
^
compilation terminated.
error: command 'x86_64-linux-gnu-gcc' failed with exit status 1
----------------------------------------
Failed building wheel for cffi
and ...
build/temp.linux-x86_64-2.7/_openssl.c:423:30: fatal error: openssl/opensslv.h: No such file or directory
#include <openssl/opensslv.h>
^
compilation terminated.
error: command 'x86_64-linux-gnu-gcc' failed with exit status 1
----------------------------------------
Failed building wheel for cryptography
Those packages are needed to build the
cffi
andcryptography
wheels. Without them, the following errors are thrown:and ...