def is_private_name(name_string):
    """
    Check if this string is written in a private/protected reference python convention
    Args:
        name_string (str):

    Returns (Bool): True if variable begins with "_", False otherwise

    Examples:
        >>> is_private_name("_some_var_name")
        True
        >>> is_private_name("some_var_name")
        False
    """
    return name_string.startswith('_')
