class Github::PullRequests

def commits(user_name, repo_name, request_id, params={})
  _update_user_repo_params(user_name, repo_name)
  _validate_user_repo_params(user, repo) unless user? && repo?
  _validate_presence_of request_id
  _normalize_params_keys(params)
  # _merge_mime_type(:pull_request, params)
  response = get_request("/repos/#{user}/#{repo}/pulls/#{request_id}/commits", params)
  return response unless block_given?
  response.each { |el| yield el }
end