import re

def is_valid_phone_number(phone_number):
    if not phone_number:
        return False
    
    pattern = r'^09\d{9}$'
    return bool(re.match(pattern, phone_number))



def is_valid_email(email):
    pattern = r'^[\w\.-]+@[\w\.-]+\.\w+$'
    return re.match(pattern, email)