def select_header_accept(accepts)
      return nil if accepts.nil? || accepts.empty?
      # use JSON when present, otherwise use all of the provided
      json_accept = accepts.find { |s| json_mime?(s) }
      json_accept || accepts.join(',')
    end
def select_header_accept(accepts)
      return nil if accepts.nil? || accepts.empty?
      # use JSON when present, otherwise use all of the provided
      json_accept = accepts.find { |s| json_mime?(s) }
      json_accept || accepts.join(',')
    end
Return Accept header based on an array of accepts provided.
 @param [Array] accepts array for Accept
 @return [String] the Accept header (e.g. application/json)