Проблема создания потоков с уникальными запросами

Question

Я пытаюсь реализовать многопоточность внутри класса для подключения к API платформы мониторинга и создания пакетов потоков для нескольких уникальных HTTP-запросов.

Проблема в функции Monitor.load_requests ().

Я выполнил различную отладку, уменьшил количество запросов, обрабатываемых сценарием, до 1 и напечатал имя потока, но я не вижу, что передается в threading.Thread.start ().

import json
import os
import requests
from queue import Queue
import threading
import urllib3
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)


var_config_file = 'variables.json'


class LoadSourceFile(object):
    """Obtain the absolute path and open any given filename, open the file and return the data"""
    def __init__(self):
        """TBC"""

    def open_file(self, name):
        """Open the specified file, if it exists and output the data it contains."""
        filename = self.get_full_pathname(name)
        if os.path.exists(filename):  # If the program can find the JSON file, read it into memory.
            with open(name) as var_conf_fh:
                data = json.load(var_conf_fh)
            return data
        else:
            print('Error: File / path', filename, 'not found!')

    @staticmethod
    def get_full_pathname(name):
        """Obtain the absolute path and open any given filename."""
        file_path = os.path.abspath(os.path.join('.', name))
        return file_path


class Monitor(object):
    """Primary worker function."""
    def __init__(self):
        """Read in variables from external file."""
        self.load_file = LoadSourceFile()
        self.api_vars = self.load_file.open_file(var_config_file)  # Obtain variables from variable_config.json.
        self.protocol = self.api_vars['protocol']
        self.api_method_get = 'get'
        self.api_method_post = 'post'
        self.uname = self.api_vars['monitor_uname']
        self.pword = self.api_vars['monitor_pword']
        self.headers = {'App-Key': self.api_vars['monitor_api_key'], 'Content-Type': 'application/json'}
        self.monitor_url = self.api_vars['monitor_api_url']
        self.monitor_version = self.api_vars['monitor_api_version']
        self.monitor_path = self.api_vars['monitor_api_url_path']
        self.queuing = Queue()

    def construct_url(self):
        """Create the correct monitor API URL format from the variable.json file."""
        api_url = self.protocol + self.monitor_url + self.monitor_version + self.monitor_path
        return api_url

    def check_get_summary(self):
        """Return a summary dictionary of the monitor checks."""
        monitor_check_summ_url = self.construct_url()  # Get the URL.
        monitor_check_summary = self.load_requests(self.api_method_get, [monitor_check_summ_url], self.uname,
                                                   self.pword, self.headers)
        return monitor_check_summary

    @staticmethod
    def api_connect(*args):
        api_method = args[0]
        api_url_list = args[1]
        uname = args[2]
        pword = args[3]
        for api_url in api_url_list:
            try:
                if args.__len__() == 5 and api_method == 'get':
                    headers = args[4]
                    try:
                        data = requests.get(api_url, auth=HTTPBasicAuth(uname, pword), headers=headers,
                                            verify=False).text
                        return data
                    except json.JSONDecodeError as err:
                        print('Error', err)
                else:
                    data = 'Wrong number of arguments.'
                    return data
            # finally:
                # self.queuing.task_done()
            except json.JSONDecodeError as err:
                print('Error', err)

    def load_requests(self, *args):
        """Populate queue with list of requests."""
        api_method = args[0]
        api_url_list = args[1]
        uname = args[2]
        pword = args[3]
        headers = args[4]

        for api_url in api_url_list:
            self.queuing.put([api_url])

        while not self.queuing.empty():
            for t in range(0, 10):
                t = threading.Thread(target=self.api_connect(api_method, api_url_list, uname, pword, headers))
                t.setDaemon(True)
                t.start()
                t.join()
                self.queuing.join()


def main():
    monitor_operations = Monitor()
    result = monitor_operations.check_get_summary()
    print('Result: ', result)


if __name__ == '__main__':
    main()

Список запросов (только один в этом первом экземпляре) должен быть помещен в отдельные потоки, но я получаю ошибку при t.start (), утверждающую, что объект str не может быть вызван.

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/local/Cellar/python/3.7.3/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "/usr/local/Cellar/python/3.7.3/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py", line 865, in run
    self._target(*self._args, **self._kwargs)
TypeError: 'str' object is not callable```