def is_phone_number(text: str) -> bool:
    """Checks for phone numbers in the text.

    Args:
        text (str): The text being passed to be checked for phone numbers

    Returns:
        bool: Whether the text is a phone number.
    """
    if len(text) != 12:
        return False
    for i in range(0, 3):
        if not text[i].isdecimal():
            return False
    if text[3] != "-":
        return False
    for i in range(4, 7):
        if not text[i].isdecimal():
            return False
    if text[7] != "-":
        return False
    for i in range(8, 12):
        if not text[i].isdecimal():
            return False
    return True


message = "Call me at 415-555-1011 tomorrow. 415-555-9999 is my office."
for i in range(len(message)):
    chunk = message[i:i+12]
    if is_phone_number(chunk):
        print("Phone number found: " + chunk)
print("Done.")
