def extract_handles_from_mentioner(mentioner)
      content = extract_mentioner_content(mentioner)
      handles = content.scan(handle_regexp).map { |handle| handle.gsub("#{mention_prefix}","") }
    end
def extract_handles_from_mentioner(mentioner)
      content = extract_mentioner_content(mentioner)
      handles = content.scan(handle_regexp).map { |handle| handle.gsub("#{mention_prefix}","") }
    end
Extract handles from mentioner

 @param [Mentioner] mentioner - the {Mentioner} to extract handles from
 @return [Array]