Change variable in Layout from view script
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in my layout i have things like meta tags etc. that may change in e.g. in different static sites.

Example:
if i go to
/static/about
i would like to have a different meta-description as in
/static/contact

My Problem is that i would like to change these variables/values inside the view script static/content/about or static/content/contact and NOT in the controller.

How can i do that?