Requests 2.21.0 doesn't recognise unicode filenames for uploads

In python 2 unicode filenames are not recognized. 
When trying to send a file with a file name containing unicode chars (e.g. ", Γ etc) the request is sent without the file. 

## Expected Result

The request is sent containing the file

## Actual Result

The request is sent without the file 

## Reproduction Steps

```python
import requests
 f= open('/<file-path>/sample-Γ.pdf','rb')
 r = requests.request('POST',URL, files={'sample': f})
```

## System Information

    $ python -m requests.help

```
{
  "chardet": {
    "version": "3.0.4"
  }, 
  "cryptography": {
    "version": ""
  }, 
  "idna": {
    "version": "2.8"
  }, 
  "implementation": {
    "name": "CPython", 
    "version": "2.7.10"
  }, 
  "platform": {
    "release": "17.7.0", 
    "system": "Darwin"
  }, 
  "pyOpenSSL": {
    "openssl_version": "", 
    "version": null
  }, 
  "requests": {
    "version": "2.21.0"
  }, 
  "system_ssl": {
    "version": "20000000"
  }, 
  "urllib3": {
    "version": "1.24.1"
  }, 
  "using_pyopenssl": false
}```



How did you verify there's no request body?

Everything you provided works locally for me so it's most likely your server that's misbehaving.

We tested it via postman prior to opening this issue - when using postman, the server received the file containing the unicode char in its name with no issues, however when we used requests package (for python 2), we were able to send a file that does not contain any unicode chars in its file name, however when we tried sending a file with a unicode char in its name we faced the issues described above - the file was not received in the server.

This behavior reproduces across multiple systems, operating systems and networks, so it's unlikely this is due to a local configuration...

The verification was done in the server - whenever we sent a request without a file we'd receive an error code in the response. It should be noted the file was accessed via a key ('sample'), and not directly in the body - it's possible this issue is related to the key.

That's hardly enough information to be helpful here. Also, the issues states it was sent without the file, but it doesn't seem you verified that via `r.request.body`

Could you verify this against some other server, e.g., httpbin.org?

Sure thing, will do it now

The response was as follows (using response.json()):
```
{u'files': {u'sample': u''}, u'origin': u'172.17.0.1', u'form': {}, u'url': u'http://localhost/post', u'args': {}, u'headers': {u'Content-Length': u'161', u'Accept-Encoding': u'gzip, deflate', u'Host': u'localhost', u'Accept': u'*/*', u'User-Agent': u'python-requests/2.19.1', u'Connection': u'keep-alive', u'Content-Type': u'multipart/form-data; boundary=8b7752cc729c052ab5db28697b545503'}, u'json': None, u'data': u''}
```
The response for the same file using postman was:
```
{
    "args": {},
    "data": "",
    "files": {
        "sample": "data:application/pdf;base64,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"
    },
    "form": {},
    "headers": {
        "Accept": "application/json",
        "Accept-Encoding": "gzip, deflate",
        "Cache-Control": "no-cache",
        "Connection": "keep-alive",
        "Content-Length": "3246",
        "Content-Type": "multipart/form-data; boundary=--------------------------554121099512621829342169",
        "Host": "localhost:80",
        "Postman-Token": "4adf795c-00f7-454b-b9a8-1876ae65e33d",
        "User-Agent": "PostmanRuntime/7.4.0",
        "X-Api-Key": "da758758d5c44f9687263f05a855054e",
        "X-Api-Secret": "21f6aa272a2926c7fc691769927416c0c4957da507fb4ff2105bd161581f5b1e"
    },
    "json": null,
    "origin": "172.17.0.1",
    "url": "http://localhost:80/post"
}
```

The file we used is this one:
[sample-Γ.pdf](https://github.com/requests/requests/files/2718454/sample-.pdf)


And what do you see in `response.request.body`?

I ask because

```
Python 2.7.15 (default, Oct 15 2018, 15:26:09) 
[GCC 8.2.1 20180801 (Red Hat 8.2.1-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import requests
>>> fd = open('./sample-Γ.pdf', 'rb')
>>> r = requests.post('https://httpbin.org/post', files={'sample': fd})
>>> r.json()['files']
{u'sample': u'data:application/octet-stream;base64,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'}
>>> print(requests.__version__)
2.21.0
```

Also your User-Agent says:

```
 u'User-Agent': u'python-requests/2.19.1'
```

Which seems like this is more a problem with something in your environment

You are right, once I updated the package to version 2.21 the issue was resolved...

You can close this issue.