Pipeline in Python w/o invoking the shell: username = input("Hello, what's your name? ") p1 = Popen(["figlet", f"Welcome, {username}"], stdout=PIPE)

Pipeline in Python w/o invoking the shell: username = input("Hello, what's your name? ") p1 = Popen(["figlet", f"Welcome, {username}"], stdout=PIPE) p2 = Popen(["lolcat", "-f"], stdin=p1.stdout, stdout=PIPE) p1.stdout.close() # Allow p1 to receive a SIGPIPE if p2 exits. banner = p2.communicate()[0] print(banner) https://docs.python.org/3/library/subprocess.html#replacing-shell-pipeline https://docs.python.org/3/library/subprocess.html#replacing-... Don't use the shell unless you absolutely have to, and when you do have to, use shlex.quote for quoting arguments: https://docs.python.org/3/library/shlex.html#shlex.quote https://docs.python.org/3/library/shlex.html#shlex.quote username = input("Hello, what's your name? ") banner = check_output(f"figlet "Welcome, {quote(username)}" | lolcat -f", shell=True) print(banner) For something this simple, you could also just use `subprocess.check_output` twice: username = input("Hello, what's your name? ") banner = check_output(["figlet", f"Welcome, {username}"]) banner = check_output(["lolcat", "-f"], input=banner) print(banner)