Can't parse version information, urllib3 returns "['dev']"

I wrote a script and tried to execute it. The python interpreter stopped the execution with a traceback saying that
```
Traceback (most recent call last):
  File ".\main.py", line 3, in <module>
    import lyricsgetter
  File "C:\Users\smart\Documents\Projects\telegram-lyrics-bot\lyricsgetter.py", line 1, in <module>
    import requests
  File "C:\Users\smart\AppData\Local\Programs\Python\Python36\lib\site-packages\requests\__init__.py", line 53, in <module>
    major, minor, patch = urllib3_version
ValueError: not enough values to unpack (expected 3, got 1)
```
I then tried adding a `print(urllib3_version)` before line 53 in `__init__.py`. 

## Expected Result

`print(urllib3_version)` should have returned the version, and my script should have executed fine.

## Actual Result

`print(urllib3_version)` printed `['dev']` and stopped the execution of my script with a `ValueError`

## Reproduction Steps

```python
import requests
```

## System Information

    $ python -m requests.help

```
['1', '21', '1']          
{                         
  "chardet": {            
    "version": "3.0.4"    
  },                      
  "cryptography": {       
    "version": ""         
  },                      
  "implementation": {     
    "name": "CPython",    
    "version": "3.6.0"    
  },                      
  "platform": {           
    "release": "10",      
    "system": "Windows"   
  },                      
  "pyOpenSSL": {          
    "openssl_version": "",
    "version": null       
  },                      
  "requests": {           
    "version": "2.17.3"   
  },                      
  "system_ssl": {         
    "version": "100020af" 
  },                      
  "urllib3": {            
    "version": "1.21.1"   
  },                      
  "using_pyopenssl": false
}                         
```

That's quite fascinating especially given the output of `python -m requests.help` as you printed it which shows `urllib3` at version 1.21.1 and even `urllib3_version` as `['1', '21', '1']`.

Hey @Ichicoro, this is actually a duplicate of #4076. I'm in the process of finishing a PR to address this so it should be fixed in an upcoming release. Thanks for taking the time to make sure this was documented.

Can you share any of your code in the traceback?

@nateprewitt this is related but different I think

`telegram-lyrics-bot` is using `python-telegram-bot` which vendors a custom version of urllib3. The vendored version has a `__version__` of `dev` which is what's causing this.

@sigmavirus24 Do you mean the code from my install of `requests` or from my project?

Ah I see @nateprewitt. @Ichicoro, @nateprewitt is in fact correct that this is a duplicate.

I am also getting this error at the moment. I don't understand why there is defintly urllib3 in version 1.21.1 installed, but in my code requests wants to import urllib3 in version ['dev']. I just don't get it. There is just one version of urllib3 installed in my virtualenv. 


@fuuman Are you using anything that patches or overrides urllib3, e.g. `telegram`?

Yeah, I am using the [python-telegram-bot wrapper](https://github.com/python-telegram-bot/python-telegram-bot).

@fuuman Ok, see #4076, which reveals that telegram is aliasing your copy of urllib3.