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: Find a member in the group.
  
  Parameters
  ----------
  item : str
      The member to find the group.
  
  Returns
  -------
  member_exists : bool
      Flag indicating whether or not the member is in the group.
code: def member(self, item):
      r"""Find a member in the group.
  
      Parameters
      ----------
      item : str
          The member to find the group.
  
      Returns
      -------
      member_exists : bool
          Flag indicating whether or not the member is in the group.
  
      """
      return item in self.members
  
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 4 for calling the Group obj's underlying member method code with example usage: obj.member(item) and returns: unknown