def _input_wrap(prompt, default=None):
    """
    Run input() with formatted prompt, and return
    The while loop can be used to ensure correct output
    """
    understood = False
    while not understood:
        result = input(prompt.format(default=default)).lower().strip()
        if result in {"y", "yes"}:
            return True
        if result in {"n", "no"}:
            return False
        if not result:
            return default
        if result in {"quit", "q", "exit"}:
            raise RuntimeError("User quit.")
        if not isinstance(default, bool):
            return result
        print("Error: answer not understood. You can 'quit' or hit ctrl+c to exit.")