As you mentioned, the easiest way is to use raw_input() (or simply input() for Python 3). There is no built-in way to do this. From Recipe 577058:

import sys


def query_yes_no(question, default="yes"):
    """Ask a yes/no question via raw_input() and return their answer.

    "question" is a string that is presented to the user.
    "default" is the presumed answer if the user just hits <Enter>.
            It must be "yes" (the default), "no" or None (meaning
            an answer is required of the user).

    The "answer" return value is True for "yes" or False for "no".
    """
    valid = {"yes": True, "y": True, "ye": True, "no": False, "n": False}
    if default is None:
        prompt = " [y/n] "
    elif default == "yes":
        prompt = " [Y/n] "
    elif default == "no":
        prompt = " [y/N] "
    else:
        raise ValueError("invalid default answer: '%s'" % default)

    while True:
        sys.stdout.write(question + prompt)
        choice = input().lower()
        if default is not None and choice == "":
            return valid[default]
        elif choice in valid:
            return valid[choice]
        else:
            sys.stdout.write("Please respond with 'yes' or 'no' " "(or 'y' or 'n').\n")

(For Python 2, use raw_input instead of input.) Usage example:

>>> query_yes_no("Is cabbage yummier than cauliflower?")
Is cabbage yummier than cauliflower? [Y/n] oops
Please respond with 'yes' or 'no' (or 'y' or 'n').
Is cabbage yummier than cauliflower? [Y/n] [ENTER]
>>> True

>>> query_yes_no("Is cabbage yummier than cauliflower?", None)
Is cabbage yummier than cauliflower? [y/n] [ENTER]
Please respond with 'yes' or 'no' (or 'y' or 'n').
Is cabbage yummier than cauliflower? [y/n] y
>>> True

If there's only one enter required, just use echo and a pipe:

echo | python script.py

echo prints an empty line (with newline) to standard output, and then we redirect that into the input of the Python script using |. When Python reads from standard input it will get an empty line and continue.

If the script wants more than one enter press, you can use the yes command and a pipe:

yes "" | python script.py

The yes command prints the same line to standard output over and over forever. By default the string is y, but here we make it an empty string so it's just newlines forever.

If the enter is required as a response to a particular prompt, and at other times you need different input, use expect, which is "a Tcl extension that lets you automate interactions with interactive programs".

It is possible to write your shell script so that it reads from Python's output and produces new input for it, but I don't especially recommend it. If you want to do that, see IO Redirection in the Advanced Bash Scripting Guide: you will need to clone file descriptors to do that. You can also use mkfifo and make named pipe files, then read from and write to them normally.

To be honest, I would start thinking about alternative approaches if you're reaching the point of doing either of these approaches: shell scripting just isn't built for this and it'll be much more straightforward to write your script in, say, Python itself.

• characters should be named Character
• Add some type hints
• Use f-strings
• Use int or float for power score, not str
• Use a @property where appropriate
• As-is, there isn't a lot of advantage to separating your prompt strings into variables
• For the data method, don't force a print - just return a string and print at the outer level
• Add a main
• Square brackets around an input choice implies that it is the default to be selected on 'enter'
• Simplify your yes/no check to only care about the first letter; anything more complicated isn't all that useful
• Add an input validation loop

Suggested:

class Character:
    def __init__(
        self,
        title: str,
        name: str,
        power_score: int,
        biography: str = 'Not much is known about this character',
    ):
        self.title = title
        self.name = name
        self.power_score = power_score
        self.biography = biography

    @property
    def full_name(self) -> str:
        return f'{self.title} {self.name}'

    @property
    def data(self) -> str:
        return (
            f'{self.title} {self.name} | Power score - {self.power_score} -\n'
            f'{self.biography}'
        )


def ascii_art():
    # Y(Height) of ascii-art
    z = 12
    for x in range(z):
        hyphens = "-" * (z-x)
        print(hyphens + "*" * x + " " * x + hyphens)


def input_yesno(prompt: str) -> bool:
    full_prompt = f'{prompt} ([Yes]/No): '
    while True:
        answer = input(full_prompt).strip()
        if answer == '':
            return True

        answer = answer[0].lower()
        if answer == 'y':
            return True
        if answer == 'n':
            return False
        print('ERROR')


def main():
    ascii_art()
    if not input_yesno('Are you ready to play'):
        return

    is_hero = input_yesno('Do you want to be a Hero')
    print('\nYou have selected', end=' ')
    if is_hero:
        print('to be a hero')
        character = Character('Barbarian', 'Cider', 4854)
    else:
        print('not to be a hero')
        character = Character('Lord', 'Cido', 7910)

    print("\nYour character's profile:")
    print(character.data)


if __name__ == '__main__':
    main()

In Python 3, use input():

input("Press Enter to continue...")

In Python 2, use raw_input():

raw_input("Press Enter to continue...")

This only waits for the user to press enter though.

On Windows/DOS, one might want to use msvcrt. The msvcrt module gives you access to a number of functions in the Microsoft Visual C/C++ Runtime Library (MSVCRT):

import msvcrt as m
def wait():
    m.getch()

This should wait for a key press.

Notes:

In Python 3, raw_input() does not exist.
In Python 2, input(prompt) is equivalent to eval(raw_input(prompt)).