Install python 3.7 + pip in linux mint 19 cinnamon

install-python-3-pip-linux-mint-19.sh

#Step 1 : preconditions
sudo apt-get install build-essential checkinstall
sudo apt-get install libreadline-gplv2-dev libncursesw5-dev libssl-dev \
    libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev libffi-dev 

#Step 2: download an unpack python
cd /usr/src
sudo wget https://www.python.org/ftp/python/3.7.2/Python-3.7.2.tgz
sudo tar xzf Python-3.7.2.tgz

#Step 3 : compile
cd Python-3.7.2
sudo ./configure --enable-optimizations
#use altinstall used to keep original python, if no python environment use sudo make install
sudo make altinstall 

this doesn't installs pip

Try sudo apt install python3-pip manually.