Ability to condition a DFF according to Legal Entity

Summary:

Ability to condition a DFF according to Legal Entity

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Our customer would like to defaults the value of a created Context Segment (in Assignment Attributes - PER_ASG_DF) to the selected Legal Entity. 

In detail, if the L.E. entered belongs to the country Germany, the Context Segment "Country-specific localisations" must be automatically defaulted to the country DE (created in "manage context").

How can we achieve this?

Thanks

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