在 bash 中，我可以使用该help命令打印特定内置命令的概要
$ help pwd
pwd: pwd [-LP]
Print the name of the current working directory.
Options:
-L print the value of $PWD if it names the current working
directory
-P print the physical directory, without any symbolic links
By default, `pwd' behaves as if `-L' were specified.
Exit Status:
Returns 0 unless an invalid option is given or the current directory
cannot be read.
zsh中是否有等价物，还是我只使用man zshbuiltins？