Validate phone number

Use regex patterns to verify if a phone number is valid.

regex validation phone

Write a function `is_valid_phone_number(s: str) -> bool` that returns `True` if the input string `s` is a valid US-style phone number, and `False` otherwise.

A valid phone number must follow one of these exact formats:
- `(XXX) XXX-XXXX` (with parentheses, a space after the closing parenthesis, and a hyphen)
- `XXX-XXX-XXXX` (hyphens between groups)
- `XXX.XXX.XXXX` (dots between groups)
- `+1 XXX XXX XXXX` (with country code, spaces between groups)

Each `X` is a digit from 0-9. No other characters (like letters, extra spaces, or parentheses in other positions) are allowed. Leading/trailing spaces in the input are allowed and should be ignored.

Use the `re` module to implement your check.

Constraints

- The input string length is between 0 and 50.
- The input contains only printable ASCII characters.
- Your function should be efficient; the `re.fullmatch` or similar approach is sufficient.

Example

```python
>>> is_valid_phone_number("(123) 456-7890")
True
>>> is_valid_phone_number("123-456-7890")
True
>>> is_valid_phone_number("123.456.7890")
True
>>> is_valid_phone_number("+1 123 456 7890")
True
>>> is_valid_phone_number("1234567890")
False
>>> is_valid_phone_number("(123)456-7890")
False
```

10 points ~15 min

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Hints

Use `re.fullmatch` to match the entire string after stripping whitespace.

Combine all four patterns into one regex with alternation (`|`).

Remember to escape special characters like parentheses and dots in the regex.

Use `\d` to match any digit.

Test Results

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