ERROR: Could not find a version that satisfies the requirement fastapi (from versions: none)

Question

I am setting up a python environment on my laptop which is behind a corporate firewall. After getting all the proxy settings fixed, I was able to use virtualenv to create an environment. I then tested by installing fastapi and uvicorn. That went well until I created a new virtualenv in another folder and now I get the error

ERROR: Could not find a version that satisfies the requirement fastapi (from versions: none)

ERROR: No matching distribution found for fastapi

It seems that I get the error for some packages and not others. For example install pip install flask works just fine. If I then try to install flask in another environment I get the same error.

My Python Version: Python 3.8.3

My pip version: pip 20.2.3

OS: Windows 10

Below I have the failed results for fastapi and below that the successful result of installing python-dotenv, which I had not instlled before.

Here is the verbose output of trying to install fastapi

 pip -v install --proxy http://10.108.19.5:3128 fastapi
Using pip 20.2.3 from C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip (python 3.8)
Non-user install because user site-packages disabled
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-ephem-wheel-cache-ocbqxum9
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-7zbqpgxd
Initialized build tracking at C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-7zbqpgxd
Created build tracker: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-7zbqpgxd
Entered build tracker: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-7zbqpgxd
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-install-ozn8129j
1 location(s) to search for versions of fastapi:
* https://pypi.org/simple/fastapi/
Fetching project page and analyzing links: https://pypi.org/simple/fastapi/
Getting page https://pypi.org/simple/fastapi/
Found index url https://pypi.org/simple
Looking up "https://pypi.org/simple/fastapi/" in the cache
Request header has "max_age" as 0, cache bypassed
Starting new HTTPS connection (1): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Incremented Retry for (url='/simple/fastapi/'): Retry(total=4, connect=None, read=None, redirect=None, status=None)
Retry: /simple/fastapi/
Resetting dropped connection: pypi.org
Starting new HTTPS connection (2): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Incremented Retry for (url='/simple/fastapi/'): Retry(total=3, connect=None, read=None, redirect=None, status=None)
Retry: /simple/fastapi/
Resetting dropped connection: pypi.org
Starting new HTTPS connection (3): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Incremented Retry for (url='/simple/fastapi/'): Retry(total=2, connect=None, read=None, redirect=None, status=None)
Retry: /simple/fastapi/
Resetting dropped connection: pypi.org
Starting new HTTPS connection (4): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Incremented Retry for (url='/simple/fastapi/'): Retry(total=1, connect=None, read=None, redirect=None, status=None)
Retry: /simple/fastapi/
Resetting dropped connection: pypi.org
Starting new HTTPS connection (5): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Incremented Retry for (url='/simple/fastapi/'): Retry(total=0, connect=None, read=None, redirect=None, status=None)
Retry: /simple/fastapi/
Resetting dropped connection: pypi.org
Starting new HTTPS connection (6): pypi.org:443
https://pypi.org:443 "GET /simple/fastapi/ HTTP/1.1" 500 655
Could not fetch URL https://pypi.org/simple/fastapi/: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/fastapi/ (Caused by ResponseError('too many 500 error responses')) - skipping
Given no hashes to check 0 links for project 'fastapi': discarding no candidates
ERROR: Could not find a version that satisfies the requirement fastapi (from versions: none)
ERROR: No matching distribution found for fastapi
Exception information:
Traceback (most recent call last):
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\cli\base_command.py", line 228, in _main
    status = self.run(options, args)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\cli\req_command.py", line 182, in wrapper
    return func(self, options, args)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\commands\install.py", line 323, in run
    requirement_set = resolver.resolve(
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 183, in resolve
    discovered_reqs.extend(self._resolve_one(requirement_set, req))
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 388, in _resolve_one
    abstract_dist = self._get_abstract_dist_for(req_to_install)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 339, in _get_abstract_dist_for
    self._populate_link(req)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 305, in _populate_link
    req.link = self._find_requirement_link(req)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 270, in _find_requirement_link
    best_candidate = self.finder.find_requirement(req, upgrade)
  File "C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip\_internal\index\package_finder.py", line 926, in find_requirement
    raise DistributionNotFound(
pip._internal.exceptions.DistributionNotFound: No matching distribution found for fastapi
1 location(s) to search for versions of pip:
* https://pypi.org/simple/pip/
Fetching project page and analyzing links: https://pypi.org/simple/pip/
Getting page https://pypi.org/simple/pip/
Found index url https://pypi.org/simple
Looking up "https://pypi.org/simple/pip/" in the cache
Request header has "max_age" as 0, cache bypassed
Starting new HTTPS connection (1): pypi.org:443
https://pypi.org:443 "GET /simple/pip/ HTTP/1.1" 500 655
Could not fetch URL https://pypi.org/simple/pip/: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by ResponseError('too many 500 error responses')) - skipping
Given no hashes to check 0 links for project 'pip': discarding no candidates
Removed build tracker: 'C:\\Users\\simon.carr2\\AppData\\Local\\Temp\\pip-req-tracker-7zbqpgxd'

and if I install something I have not installed before it works.

pip -v install --proxy http://10.108.19.5:3128 python-dotenv
Using pip 20.2.3 from C:\dev\api_microserver_experiment\erp_microservices\ifs2004_api\lib\site-packages\pip (python 3.8)
Non-user install because user site-packages disabled
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-ephem-wheel-cache-3n6r96jd
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-hxciblsu
Initialized build tracking at C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-hxciblsu
Created build tracker: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-hxciblsu
Entered build tracker: C:\Users\simon.carr2\AppData\Local\Temp\pip-req-tracker-hxciblsu
Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-install-jhqdyshv
1 location(s) to search for versions of python-dotenv:
* https://pypi.org/simple/python-dotenv/
Fetching project page and analyzing links: https://pypi.org/simple/python-dotenv/
Getting page https://pypi.org/simple/python-dotenv/
Found index url https://pypi.org/simple
Looking up "https://pypi.org/simple/python-dotenv/" in the cache
Request header has "max_age" as 0, cache bypassed
Starting new HTTPS connection (1): pypi.org:443
https://pypi.org:443 "GET /simple/python-dotenv/ HTTP/1.1" 200 None
Updating cache with response from "https://pypi.org/simple/python-dotenv/"
Caching b/c date exists and max-age > 0
  Found link https://files.pythonhosted.org/packages/ad/3b/16a207ced20a1be0cc2ec5a53ab68ce1976ad643fe7f135d3addd763abf0/python-dotenv-0.1.0.tar.gz#sha256=26156022355d4457bc9062bcead7fde4824623d4463488b623bdd5ce912462fa (from https://pypi.org/simple/python-dotenv/), version: 0.1.0
  Found link https://files.pythonhosted.org/packages/e6/95/e9239c25d2c06c4a262360375d4e0c61b243d1c763d647137aca4d7df9fe/python-dotenv-0.1.2.tar.gz#sha256=aaefda0e975b702374f7c86edcf948590bd4f47737b33027de1bc72afbed745b (from https://pypi.org/simple/python-dotenv/), version: 0.1.2
  Found link https://files.pythonhosted.org/packages/9c/b8/b9c1dbc7fec4ddf85d1c5aed117e8a8393315378ad2100147304ec610c89/python_dotenv-0.1.2-py2.py3-none-any.whl#sha256=b2c451a7127d1ae2b2d5d5977c10f3e0c4892b4954ddd62fe3d9714bf12a2cfc (from https://pypi.org/simple/python-dotenv/), version: 0.1.2
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  Found link https://files.pythonhosted.org/packages/d1/2f/25a275868f3efd92a0009b906b9528317f3fa1689ce129ead705cc31e3e4/python-dotenv-0.2.0.tar.gz#sha256=88f1d4dc6586bed44d32361ee9866e23503fc93ebc80979d3bbca3fdace56716 (from https://pypi.org/simple/python-dotenv/), version: 0.2.0
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  Found link https://files.pythonhosted.org/packages/c8/29/774774f808d25bb2a2f43c7bc07b00084a7dd06e2cb48c181acc1c3e80c7/python_dotenv-0.11.0-py2.py3-none-any.whl#sha256=ca9f3debf2262170d6f46571ce4d6ca1add60bb93b69c3a29dcb3d1a00a65c93 (from https://pypi.org/simple/python-dotenv/), version: 0.11.0
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  Found link https://files.pythonhosted.org/packages/33/3d/a0c00002bae69321f5b87ea7ed123ddf1933e09d3ff658d277889698ee59/python-dotenv-0.14.0.tar.gz#sha256=8c10c99a1b25d9a68058a1ad6f90381a62ba68230ca93966882a4dbc3bc9c33d (from https://pypi.org/simple/python-dotenv/), version: 0.14.0
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Given no hashes to check 62 links for project 'python-dotenv': discarding no candidates
Using version 0.14.0 (newest of versions: 0.1.0, 0.1.2, 0.1.3, 0.1.5, 0.2.0, 0.3.0, 0.4.0, 0.5.0, 0.5.1, 0.6.0, 0.6.1, 0.6.2, 0.6.3, 0.6.4, 0.6.5, 0.7.0, 0.7.1, 0.8.0, 0.8.1, 0.8.2, 0.9.0, 0.9.1, 0.10.0, 0.10.1, 0.10.2, 0.10.3, 0.10.4, 0.10.5, 0.11.0, 0.12.0, 0.13.0, 0.14.0)
Collecting python-dotenv
  Created temporary directory: C:\Users\simon.carr2\AppData\Local\Temp\pip-unpack-ipkfgoz1
  Looking up "https://files.pythonhosted.org/packages/f2/16/28d434b28c5be29a6af8fd0e3a2bda3bd30500ef0cd17bc79f7a6793a8d4/python_dotenv-0.14.0-py2.py3-none-any.whl" in the cache
  No cache entry available
  Starting new HTTPS connection (1): files.pythonhosted.org:443
  https://files.pythonhosted.org:443 "GET /packages/f2/16/28d434b28c5be29a6af8fd0e3a2bda3bd30500ef0cd17bc79f7a6793a8d4/python_dotenv-0.14.0-py2.py3-none-any.whl HTTP/1.1" 200 17837
  Downloading python_dotenv-0.14.0-py2.py3-none-any.whl (17 kB)
  Ignoring unknown cache-control directive: immutable
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  Caching due to etag
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Installing collected packages: python-dotenv

Successfully installed python-dotenv-0.14.0
1 location(s) to search for versions of pip:
* https://pypi.org/simple/pip/
Fetching project page and analyzing links: https://pypi.org/simple/pip/
Getting page https://pypi.org/simple/pip/
Found index url https://pypi.org/simple
Looking up "https://pypi.org/simple/pip/" in the cache
Request header has "max_age" as 0, cache bypassed
Starting new HTTPS connection (1): pypi.org:443
https://pypi.org:443 "GET /simple/pip/ HTTP/1.1" 500 655
Could not fetch URL https://pypi.org/simple/pip/: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by ResponseError('too many 500 error responses')) - skipping
Given no hashes to check 0 links for project 'pip': discarding no candidates
Removed build tracker: 'C:\\Users\\simon.carr2\\AppData\\Local\\Temp\\pip-req-tracker-hxciblsu'

Answer 1

The problem was an issue on the pypi.org servers, which the 500 error in the verbose output suggested. I tried again the following morning and the issue had resolved.

I was tempted to delete this question, but I believe it might be helpful to others in the future if pypi.org has a similar outage.