docs: def visitMultiElementGroup(self, ctx: ShExDocParser.MultiElementGroupContext):
          """ multiElementGroup: unaryShape (';' unaryShape)+ ';'? """
          self.expression = EachOf(expressions=[])
          for us in ctx.unaryShape():
              parser = ShexOneOfShapeParser(self.context)
              parser.visit(us)
              self.expression.expressions.append(parser.expression)