Build curl library (tested on Ubuntu 16.04)

libcurl_ubuntu_16_04

wget https://curl.haxx.se/download/curl-7.50.0.tar.gz
tar -zxvf curl-7.50.0.tar.gz
cd curl-7.50.0/
sudo apt install libc-ares-dev
sudo apt-get install libc-ares-dev  
openssl version  # check
./configure --with-ssl=/usr/local/ssl --enable-ares
make
sudo make install
curl --version
which curl
export PYCURL_SSL_LIBRARY=openssl
export PYCURL_CURL_CONFIG=/usr/local/bin/curl-config
export LD_LIBRARY_PATH=/usr/local/lib
pip uninstall pycurl
pip install --compile pycurl