BUG: DataFrame to_csv compression with 'zip' use zipfilename as archive name
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---


```python
a=pd.DataFrame({'a':[1,2,3,4,5],'b':[4,5,6,7,8]})
a.to_csv('myfile.csv.zip')
```

#### Problem description

when use gzip method, the function works fine, a.to_csv('myfile.csv.gz') will create a gzip file with an archive file named myfile.csv.  
the "zip" method works bad,a.to_csv('myfile.csv.zip') will create a zipfile with an archive file named myfile.csv.zip 



