The purpose of this mapping is to define a heterogeneous set of fields that belong to some modules. Simply a bunch of fields. This could be used to define a set of fields to launch a mass operation upon or a set of fields which must be excluded/included from some global process.

The accepted format is:

	  <info>anything you need</info>

You will be able to get the set of fields using the getFieldSet() method, and the fields on one module with the getFieldSetModule($module) method.

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