code: def unhide_tool(self, context_name, tool_name):
          
          data = self._context(context_name)
          hidden_tools = data["hidden_tools"]
          if tool_name in hidden_tools:
              hidden_tools.remove(tool_name)
              self._flush_tools()
docs: Unhide a tool so that it may be exposed in a suite.
  
          Note that unhiding a tool doesn't guarantee it can be seen - a tool of
          the same name from a different context may be overriding it.
  
          Args:
              context_name (str): Context containing the tool.
              tool_name (str): Name of tool to unhide.