def check_lead_zero(to_check):
    """Check if a number has a leading 0.

    Args:
        to_check (str): The number to be checked.

    Returns:
        True if a leading 0 is found or the string is empty, False otherwise.
    """
    if str(to_check) in (None, ''):
        return True
    elif str(to_check[0]) != '0':
        return False
    else:
        return True