Assume I have the folders ~/a/b in my home folder, and the folder b contains
a symbolic link to '..' named 'symlink'. Then I perform the following actions in
bash:

```
hm@mach:~$ cd a/b/symlink
hm@mach:~/a/b/symlink$ pwd -P
/home/hm/a
hm@mach:~/a/b/symlink$ cd ..
hm@mach:~/a/b$ pwd -P
/home/hm/a/b

```

pwd -P prints the current working directory, dereferencing all symbolic links.
Why is the working directory /home/hm/a/b at the end, and not /home/hm?