如何在写出csv时正确实现线程？

Question

我从Gerrit API提取提交数据，提交号在226,000范围内。我必须在每次提交时向端点发出请求，这需要花费很长时间才能理解。我想知道如何才能最好地将线程应用到我当前的流程中。

我有两个类，一个Project类，它向下钻取并检索与之关联的所有提交，并将它们保存为Commit对象，其中包含随后循环执行所需的所有信息。得到与之关联的json。我将它们全部拉到一个大的列表中，然后迭代调用get_data和write_data方法。

class Project(object):
    def __init__(self, name):
        self.name = name
        self.commits = []

    def add_commits(self, changes_list):
        for change in changes_list:
            change_id=change['change_id'],
            revision_list=change['revisions']
            self.commits.extend([Commit(rid, change_id)
                                 for rid in revision_list.keys()])

    def return_results(self, ger_obj, start=0):
        self.ger = ger_obj
        while True:
            endpoint = (r'/changes/?q=project:{project}&o=ALL_REVISIONS&'
                        r'S={num}'.format(
                project=self.name,
                num=start
            ))
            logging.info('Endpoint: {}'.format(endpoint))
            try:
                changes = ger_obj.get(endpoint)
                self.add_commits(changes_list=changes)
            except HTTPError:
                break
            start += 500
            try:
                if not changes[-1].get('_more_changes'):
                    break
            except IndexError:
                break


class Commit(object):
    def __init__(self, rev_id, change_id):
        self.rev_id = rev_id
        self.change_id = change_id

    def get_data(self, ger_obj):
        endpoint = (r'/changes/{c_id}/revisions/{r_id}/commit'.format(
            c_id=self.change_id[0],
            r_id=self.rev_id
        ))
        try:
            self.data = ger_obj.get(endpoint)
        except HTTPError as e:
            logging.warning('Endpoint: {} did not return data'.format(
                endpoint
            ))
        else:
            self.data['commitid'] = self.data.get('commit')
            self.data['name'] = self.data.get('committer')['name']
            self.data['email'] = self.data.get('committer')['email']
            self.data['date'] = self.data.get('committer')['date']
            hash = md5()
            hash.update(json.dumps(self.data).encode('utf-8'))
            self.data['etl_checksum_md5'] = hash.hexdigest()
            self.data['etl_process_status'] = ETL_PROCESS_STATUS
            self.data['etl_datetime_local'] = ETL_DATETIME_LOCAL
            self.data['etl_pdi_version'] = ETL_PDI_VERSION
            self.data['etl_pdi_build_version'] = ETL_PDI_BUILD_VERSION
            self.data['etl_pdi_hostname'] = ETL_PDI_HOSTNAME
            self.data['etl_pdi_ipaddress'] = ETL_PDI_IPADDRESS
            self.data['message'] = self.data['message'].replace('\n', ' ').replace('|', '[pipe]')

    def write_data(self, writer):
        writer.writerow(self.data)

我认为实现线程的最佳位置是我在列表中拥有所有提交并准备迭代它们：

projects = [Project(value['id']) for value in project_data.values()]
    for project in projects[:10]:
        if project.name in bad_names.keys():
            project.name = bad_names[project.name]
        project.return_results(rest)
        all_commits.extend(project.commits)

    fieldnames = get_fieldnames(
        'ods_gerrit.staging_gerrit_commits',
        REDSHIFT_POSTGRES_INFO)

    with open('testfile.csv', 'wb') as outf:
        writer = DictWriter(
        outf,
        fieldnames=fieldnames,
        extrasaction='ignore',
        delimiter='|'
    )
# Implement Threading?
        for commit in all_commits:
            commit.get_data(rest)
            try:
                commit.write_data(writer=writer)
            except AttributeError:
                continue
            except Exception:
                print commit.data, 'caused an exception.'
                continue

我已经阅读了一些线程教程，并且不确定如何正确执行此操作。我特别担心由于锁定不当而覆盖数据。