Feat/add example with multiply namespaces

[matzegebbe]

Description

This example shows a separation to different dynamic namespaces and variables loaded for the corresponding environment.
Also secrets are loaded from file (the .secrets file should never be committed)

Type of change

• New example (change which adds a new example)

All Submissions:

• Have you added an explanation of what your changes do and why you'd like us to include them?
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