Set Python System Default to 2 or 3

set_python.sh

!#/bin/bash

set_python () {
  DEFAULT_PYTHON_PATH=$(readlink /usr/bin/python)
  DEFAULT_PYTHON=${DEFAULT_PYTHON_PATH##*-}

  if [[ $1 = 2* ]]; then
    PYTHON_SET_VERSION=2
  elif [[ $1 = 3* ]]; then
    PYTHON_SET_VERSION=3
  else
    # Get user input for python version
    read -p "Enter python version [default=$DEFAULT_PYTHON]: " PYTHON_SET
    echo ""
    if [[ $PYTHON_SET = 2* ]]; then
      PYTHON_SET_VERSION=2
    elif [[ $PYTHON_SET = 3* ]]; then
      PYTHON_SET_VERSION=3
    else
      echo "Invalid python version"
      return 1
    fi
  fi

  sudo rm /usr/bin/python
  sudo ln -s /usr/bin/python$PYTHON_SET_VERSION /usr/bin/python

  echo "Setting Default Python to:"
  echo $(python -V)

}