Bump requests from 2.9.1 to 2.20.0

Bumps [requests](https://github.com/requests/requests) from 2.9.1 to 2.20.0.
- [Release notes](https://github.com/requests/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/master/HISTORY.md)
- [Commits](https://github.com/requests/requests/compare/v2.9.1...v2.20.0)

Signed-off-by: dependabot[bot] <support@github.com>

flowroutenumbersandmessaging/controllers/cdrs_controller.py

@@ -8,10 +8,8 @@
 from csv import DictReader
 import gzip
 import json
-#import StringIO
+import StringIO
-from io import StringIO
+import urllib2
-#import urllib2
-from urllib.request import urlopen
 
 from .base_controller import BaseController
 from ..api_helper import APIHelper
@@ -192,7 +190,7 @@ class CDRsController(BaseController):
             export_url = _response['data']['attributes']['download_url']
             #urllib.urlretrieve(export_url, filename)
             try:
-                response = urlopen(export_url)
+                response = urllib2.urlopen(export_url)
                 compressedFile = StringIO.StringIO(response.read())
                 decompressedFile = gzip.GzipFile(fileobj=compressedFile)
                 with open(filename, 'w') as outfile:

requirements.txt

@@ -1,4 +1,4 @@
-requests>=2.21.0
+requests==2.20.0
-jsonpickle>=0.9.6
+jsonpickle==0.7.1
 cachecontrol==0.11.7
 python-dateutil==2.5.3