def check_valid_command(command: str) -> bool:
    """
    T081 Emily Tang
    
    Checks if the user entered a valid command based on the inputted string.
    
    >>> check_valid_command("3")
    True
    >>> check_valid_command("f")
    False
    """
    # List of valid commands for the interactive user interface
    VALID_COMMANDS = ["L", "l", "S", "s", "3", "X", "x", "T", "t", "P", "p", 
                      "E", "e", "D", "d", "V", "v", "H", "h", "Q", "q"]
    # Determine if the command is valid or not
    if command in VALID_COMMANDS:
        return True
    else:
        return False