docs: def keygen(sk_file=None, pk_file=None, **kwargs):
      '''
      Use libnacl to generate a keypair.
  
      If no `sk_file` is defined return a keypair.
  
      If only the `sk_file` is defined `pk_file` will use the same name with a postfix `.pub`.
  
      When the `sk_file` is already existing, but `pk_file` is not. The `pk_file` will be generated
      using the `sk_file`.
  
      CLI Examples:
  
      .. code-block:: bash
  
          salt-call nacl.keygen
          salt-call nacl.keygen sk_file=/etc/salt/pki/master/nacl
          salt-call nacl.keygen sk_file=/etc/salt/pki/master/nacl pk_file=/etc/salt/pki/master/nacl.pub
          salt-call --local nacl.keygen
      '''
      kwargs['opts'] = __opts__
      return salt.utils.nacl.keygen(sk_file, pk_file, **kwargs)