SecurityGroupId cannot use multiple values for individual parameter

It looks like SecurityGroupId parameter only support 1 security group id. We would like to pass 2 security group ids as CommaDelimitedList type, but currently implementation doesn't support.

Is there a way to pass multiple security groups for SecurityGroupId parameter?

Start by locating the implementation that handles the SecurityGroupId parameter and CommaDelimitedList values. Check how individual parameter values are parsed and find or add tests covering multiple security group IDs; done means two IDs are accepted and passed through with documented, verified behavior.

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