one_byte_from_terminal.py

import sys
import tty
import termios


fd = sys.stdin.fileno()
# keep original terminal settings
old_settings = termios.tcgetattr(fd)


def readone():
    try:
        # set terminal to raw
        tty.setraw(sys.stdin.fileno())
        ch = sys.stdin.read(1)
    except Exception as e:
        print(e)
    finally:
        # resetting terminal for printing
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
    return ch


while True:
    ch = readone()
    chk = ord(ch)
    if chk in [3, 4]:
        # ctrl+c and ctrl+d
        break
    print(repr(ch))