Bite 215. Validate a license key

Complete the validate_license function writing a regular expression that matches a PyBites license key which:

• Starts with PB,
• following 4 times dash (-) and 8 chars which can be upper case chars or digits,
• for example: PB-U8N435EH-PG65PW87-IXPWQG5T-898XSZI4 would be a valid license key.

Return a bool (we added some type hinting for convenience).

Example how this function would work:

>>> import re
>>> from license import validate_license
>>> validate_license('PB-U8N435EH-PG65PW87-IXPWQG5T-898XSZI4')
True
>>> validate_license('pb-U8N435EH-PG65PW87-IXPWQG5T-898XSZI4')
False
>>> validate_license('bogus')
False
>>> validate_license('PB-U8N435EH-PG65PW87-IXPWQG5T-898XSZ..')
False

Have fun and code more Python!