class_docstr: Create a new Group that contains common members. All
  defined groups are stored in ``Group.groups``. Group
  names must be unique.
  
  Parameters
  ----------
  name : str
      Group name.
  space : alphapy.Space, optional
      Namespace for the given group.
  dynamic : bool, optional, default ``True``
      Flag for defining whether or not the group membership
      can change.
  members : set, optional
      The initial members of the group, especially if the
      new group is fixed, e.g., not ``dynamic``.
  
  Attributes
  ----------
  groups : dict
      Class variable for storing all known groups
  
  Examples
  --------
  
  >>> Group('tech')
docstr: Add new members to the group.
  
  Parameters
  ----------
  newlist : list
      New members or identifiers to add to the group.
  
  Returns
  -------
  None : None
  
  Notes
  -----
  
  New members cannot be added to a fixed or non-dynamic group.
code: def add(self, newlist):
      r"""Add new members to the group.
  
      Parameters
      ----------
      newlist : list
          New members or identifiers to add to the group.
  
      Returns
      -------
      None : None
  
      Notes
      -----
  
      New members cannot be added to a fixed or non-dynamic group.
  
      """
      if all([type(item) is str for item in newlist]):
          newset = set(newlist)
          if self.dynamic:
              if newset.issubset(self.members):
                  logger.info("New members already in set")
              else:
                  madd = newset - self.members
                  self.members = self.members | newset
                  logger.info("Added: %s", madd)
          else:
              logger.info("Cannot add members to a non-dynamic group")
      else:
          logger.info("All new members must be of type str")
  
file_path: AlphaPy/alphapy/group.py
imports: from alphapy.globals import USEP
  from alphapy.space import Space
  import logging
label_desc: Use image node_id 3 for calling the Group obj's underlying member method code with example usage: obj.add(newlist) without return types