import re


def check_email_format(email):
    """
    Checks that the email adheres to the rules defined by this function
    :param email:
    :return: True if ok
    """
    email_regex = re.compile(r'([a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+(\.[a-zA-Z]{2,4}))')
    if not email_regex.match(email):
        return False
    return True