We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Flesh out oldest tests
We should find the oldest versions of all our Python dependencies used in OS packages and add them to the [oldest tests](https://github.com/certbot/certbot/blob/master/tox.ini#L36) in Travis. This will prevent bugs like #3098 and #4040 from slipping into a release.

The two distros I'd check here are CentOS 7 and Debian 8.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `acme/setup.py`
Content:
```
1 import sys
2 
3 from setuptools import setup
4 from setuptools import find_packages
5 
6 
7 version = '0.16.0.dev0'
8 
9 # Please update tox.ini when modifying dependency version requirements
10 install_requires = [
11     # load_pem_private/public_key (>=0.6)
12     # rsa_recover_prime_factors (>=0.8)
13     'cryptography>=0.8',
14     # Connection.set_tlsext_host_name (>=0.13)
15     'mock',
16     'PyOpenSSL>=0.13',
17     'pyrfc3339',
18     'pytz',
19     # requests>=2.10 is required to fix
20     # https://github.com/shazow/urllib3/issues/556. This requirement can be
21     # relaxed to 'requests[security]>=2.4.1', however, less useful errors
22     # will be raised for some network/SSL errors.
23     'requests[security]>=2.10',
24     # For pkg_resources. >=1.0 so pip resolves it to a version cryptography
25     # will tolerate; see #2599:
26     'setuptools>=1.0',
27     'six',
28 ]
29 
30 # env markers cause problems with older pip and setuptools
31 if sys.version_info < (2, 7):
32     install_requires.extend([
33         'argparse',
34         'ordereddict',
35     ])
36 
37 dev_extras = [
38     'nose',
39     'tox',
40 ]
41 
42 docs_extras = [
43     'Sphinx>=1.0',  # autodoc_member_order = 'bysource', autodoc_default_flags
44     'sphinx_rtd_theme',
45 ]
46 
47 
48 setup(
49     name='acme',
50     version=version,
51     description='ACME protocol implementation in Python',
52     url='https://github.com/letsencrypt/letsencrypt',
53     author="Certbot Project",
54     author_email='client-dev@letsencrypt.org',
55     license='Apache License 2.0',
56     classifiers=[
57         'Development Status :: 3 - Alpha',
58         'Intended Audience :: Developers',
59         'License :: OSI Approved :: Apache Software License',
60         'Programming Language :: Python',
61         'Programming Language :: Python :: 2',
62         'Programming Language :: Python :: 2.6',
63         'Programming Language :: Python :: 2.7',
64         'Programming Language :: Python :: 3',
65         'Programming Language :: Python :: 3.3',
66         'Programming Language :: Python :: 3.4',
67         'Programming Language :: Python :: 3.5',
68         'Programming Language :: Python :: 3.6',
69         'Topic :: Internet :: WWW/HTTP',
70         'Topic :: Security',
71     ],
72 
73     packages=find_packages(),
74     include_package_data=True,
75     install_requires=install_requires,
76     extras_require={
77         'dev': dev_extras,
78         'docs': docs_extras,
79     },
80     entry_points={
81         'console_scripts': [
82             'jws = acme.jose.jws:CLI.run',
83         ],
84     },
85     test_suite='acme',
86 )
87
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/acme/setup.py b/acme/setup.py
--- a/acme/setup.py
+++ b/acme/setup.py
@@ -16,11 +16,7 @@
     'PyOpenSSL>=0.13',
     'pyrfc3339',
     'pytz',
-    # requests>=2.10 is required to fix
-    # https://github.com/shazow/urllib3/issues/556. This requirement can be
-    # relaxed to 'requests[security]>=2.4.1', however, less useful errors
-    # will be raised for some network/SSL errors.
-    'requests[security]>=2.10',
+    'requests[security]>=2.4.1',  # security extras added in 2.4.1
     # For pkg_resources. >=1.0 so pip resolves it to a version cryptography
     # will tolerate; see #2599:
     'setuptools>=1.0',

{"golden_diff": "diff --git a/acme/setup.py b/acme/setup.py\n--- a/acme/setup.py\n+++ b/acme/setup.py\n@@ -16,11 +16,7 @@\n     'PyOpenSSL>=0.13',\n     'pyrfc3339',\n     'pytz',\n-    # requests>=2.10 is required to fix\n-    # https://github.com/shazow/urllib3/issues/556. This requirement can be\n-    # relaxed to 'requests[security]>=2.4.1', however, less useful errors\n-    # will be raised for some network/SSL errors.\n-    'requests[security]>=2.10',\n+    'requests[security]>=2.4.1',  # security extras added in 2.4.1\n     # For pkg_resources. >=1.0 so pip resolves it to a version cryptography\n     # will tolerate; see #2599:\n     'setuptools>=1.0',\n", "issue": "Flesh out oldest tests\nWe should find the oldest versions of all our Python dependencies used in OS packages and add them to the [oldest tests](https://github.com/certbot/certbot/blob/master/tox.ini#L36) in Travis. This will prevent bugs like #3098 and #4040 from slipping into a release.\r\n\r\nThe two distros I'd check here are CentOS 7 and Debian 8.\n", "before_files": [{"content": "import sys\n\nfrom setuptools import setup\nfrom setuptools import find_packages\n\n\nversion = '0.16.0.dev0'\n\n# Please update tox.ini when modifying dependency version requirements\ninstall_requires = [\n    # load_pem_private/public_key (>=0.6)\n    # rsa_recover_prime_factors (>=0.8)\n    'cryptography>=0.8',\n    # Connection.set_tlsext_host_name (>=0.13)\n    'mock',\n    'PyOpenSSL>=0.13',\n    'pyrfc3339',\n    'pytz',\n    # requests>=2.10 is required to fix\n    # https://github.com/shazow/urllib3/issues/556. 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