Problem Statement

An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.

Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded checksum is correct. Demonstrate that your code passes the test-cases listed below.

The format of an ISIN is as follows:

For this task, you may assume that any 2-character alphabetic sequence is a valid country code. The checksum can be validated as follows:

(The comments are just informational.   Your function should simply return a Boolean result.   See #Raku for a reference solution.)

Related task:

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