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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create(url, filename):
 """Create new fMRI for given experiment by uploading local file. Expects an tar-archive. Parameters url : string Url to POST fMRI create request filename : string Path to tar-archive on local disk Returns ------- string Url of created functional data resource """

        # Upload file to create fMRI resource. If response is not 201 the
        # uploaded file is not a valid functional data archive
        files = {'file': open(filename, 'rb')}
        response = requests.post(url, files=files)
        if response.status_code != 201:
            raise ValueError('invalid file: ' + filename)
            return references_to_dict(response.json()['links'])[REF_SELF]