bash builtin command named command

$pwd
/home/jeffrin/upstream-kernel
$tail ~/.bashrc
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi
export PS1=$
function ls {
   pwd
}
$ls
/home/jeffrin/upstream-kernel
$command ls
0002-Testing-script-for-Intel-P-State-driver-crashes-duri.patch  linux    linux-kselftest  linux-kselftest.bup  linux-kselftest.bup2  linux-next  linux.old
$