code: def bind(cls, target):
  		
  		
  		if cls.__bound__ is not None:
  			return cls
  		
  		cls.__bound__ = cls.get_collection(target)
  		
  		return cls
docs: Bind a copy of the collection to the class, modified per our class' settings.
  		
  		The given target (and eventual collection returned) must be safe within the context the document sublcass
  		being bound is constructed within. E.g. at the module scope this binding must be thread-safe.