ls -l /usr/bin/python will only show the symbolic link.
ls -l /usr/bin/ | grep python2.7 to see if
python2.7 is in the directory.
The output should be something like this:
lrwxrwxrwx 1 root root 9 Jun 3 16:39 python -> python2.7 lrwxrwxrwx 1 root root 9 Jun 3 16:39 python2 -> python2.7 -rwxr-xr-x 1 root root 3550168 Jun 3 02:29 python2.7
The above shows the binary
python2.7 and two symbolic links pointing to it.