text: from typing import TYPE_CHECKING
  
  from .env_command import EnvCommand
  
  
  if TYPE_CHECKING:
      from poetry.installation.installer import Installer
  
  
  class InstallerCommand(EnvCommand):
      def __init__(self):
          self._installer = None
  
          super(InstallerCommand, self).__init__()
  
      @property
      def installer(self):  # type: () -> Installer
          return self._installer
  
      def set_installer(self, installer):  # type: (Installer) -> None
          self._installer = installer
  