def assignee=(assignee)
      @assignee = assignee.is_a?(Hash) ? Logan::Person.new(assignee) : assignee
    end
def assignee=(assignee)
      @assignee = assignee.is_a?(Hash) ? Logan::Person.new(assignee) : assignee
    end
sets the assignee for this todo

 @param [Object] assignee person hash from API or <Logan::Person> object
 @return [Logan::Person] the assignee for this todo