code: def get_pull_requests_commits(self, project, repository, pull_request_id):
          
          url = 'rest/api/1.0/projects/{project}/repos/{repository}/pull-requests/{pullRequestId}/commits'.format(
              project=project,
              repository=repository,
              pullRequestId=pull_request_id)
          params = {'start': 0}
          response = self.get(url, params=params)
          if 'values' not in response:
              return []
          commits_list = (response or {}).get('values')
          while not response.get('isLastPage'):
              params['start'] = response.get('nextPageStart')
              response = self.get(url, params=params)
              commits_list += (response or {}).get('values')
          return commits_list
docs: Get pull requests commits
          :param project:
          :param repository:
          :param pull_request_id: the ID of the pull request within the repository
          :return: