code: def _getMethodNamePrefix(self, node):
          
          targetName = node.name
          for sibling in node.parent.nodes_of_class(type(node)):
              if sibling is node:
                  # We are on the same node in parent so we skip it.
                  continue
              prefix = self._getCommonStart(targetName, sibling.name)
              if not prefix.rstrip('_'):
                  # We ignore prefixes which are just underscores.
                  continue
              return prefix
  
          return ''
docs: Return the prefix of this method based on sibling methods.
  
          @param node: the current node