upload file to my dropbox from python script

The answer of @Christina is based on Dropbox APP v1, which is deprecated now and will be turned off on 6/28/2017. (Refer to here for more information.)

APP v2 is launched in November, 2015 which is simpler, more consistent, and more comprehensive.

Here is the source code with APP v2.

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import dropbox

class TransferData:
    def __init__(self, access_token):
        self.access_token = access_token

    def upload_file(self, file_from, file_to):
        """upload a file to Dropbox using API v2
        """
        dbx = dropbox.Dropbox(self.access_token)

        with open(file_from, 'rb') as f:
            dbx.files_upload(f.read(), file_to)

def main():
    access_token = '******'
    transferData = TransferData(access_token)

    file_from = 'test.txt'
    file_to = '/test_dropbox/test.txt'  # The full path to upload the file to, including the file name

    # API v2
    transferData.upload_file(file_from, file_to)

if __name__ == '__main__':
    main()

The source code is hosted on GitHub, here.