code: def process_omp_attachements(self, node, stmt, index=None):
          
          omp_directives = metadata.get(node, OMPDirective)
          if omp_directives:
              directives = list()
              for directive in omp_directives:
                  directive.deps = [self.visit(dep) for dep in directive.deps]
                  directives.append(directive)
              if index is None:
                  stmt = AnnotatedStatement(stmt, directives)
              else:
                  stmt[index] = AnnotatedStatement(stmt[index], directives)
          return stmt
docs: Add OpenMP pragma on the correct stmt in the correct order.
  
          stmt may be a list. On this case, index have to be specify to add
          OpenMP on the correct statement.