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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add(TargetGroup, NewMember, Config=None, Args=None):
 r"""Adds members to an existing group. Args: TargetGroup (Group):
 The target group for the addition. NewMember (Group / Task):
 The member to be added. Config (dict):
 The config for the member. Args (OrderedDict):
 ArgConfig for the NewMember, if it's a task (optional). """

  Member = Task(NewMember, Args or {}, Config or {}) if isfunction(NewMember) else Group(NewMember, Config or {})
  ParentMembers = TargetGroup.__ec_member__.Members

  ParentMembers[Member.Config['name']] = Member

  alias = Member.Config.get('alias')

  if alias:
    ParentMembers[alias] = Member