docs: def import_plugin(package_name, include_available=False):
      '''
      Import MicroDrop plugin.
  
      Parameters
      ----------
      package_name : str
          Name of MicroDrop plugin Conda package.
      include_available : bool, optional
          If ``True``, import from all available plugins (not just **enabled**
          ones).
  
          By default, only the ``<conda>/etc/microdrop/plugins/enabled``
          directory is added to the Python import paths (if necessary).
  
          If ``True``, also add the ``<conda>/share/microdrop/plugins/available``
          directory to the Python import paths.
  
      Returns
      -------
      module
          Imported plugin module.
      '''
      available_plugins_dir = MICRODROP_CONDA_SHARE.joinpath('plugins',
                                                             'available')
      enabled_plugins_dir = MICRODROP_CONDA_ETC.joinpath('plugins', 'enabled')
      search_paths = [enabled_plugins_dir]
      if include_available:
          search_paths += [available_plugins_dir]
      for dir_i in search_paths:
          if dir_i not in sys.path:
              sys.path.insert(0, dir_i)
      module_name = package_name.split('.')[-1].replace('-', '_')
      return importlib.import_module(module_name)