How to check if a package is installed from Bash?

I need to check if a specific package is installed on a machine from within a Bash script.

I found something like that but I don't know how use it correctly.

dpkg -l | grep "ansible" | awk '{print $2}'
if [$? -eq 0]; then
  echo OK
else
  echo FAIL
fi

I need check, if command dpkg -l | grep "ansible" | awk '{print $2}' return me word "Ansible" then echo OK, else echo FAIL.

@EDIT

I think better will be command

dpkg -l | grep "ansible" | awk '{print $2}'

so this command return me two words:

ansible
ansible_lint

How should I use this bash script? If I doing something like that:

ansible = $?
if [$? -eq 0]; then
  echo OK
else
  echo FAIL
fi

that's not work, but I'm sure I doing that wrong. How can I read result from dpkg -l | grep "ansible" | awk '{print $2}' command and if I get word "ansible" script will print OK, if not print FAIL.