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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 experiments_fmri_download(self, experiment_id):
 """Download the fMRI data file associated with given experiment. Parameters experiment_id : string Unique experiment identifier Returns ------- FileInfo Information about fMRI file on disk or None if experiment is unknown or has no fMRI data associated with it """

        # Get experiment fMRI to ensure that it exists
        fmri = self.experiments_fmri_get(experiment_id)
        if fmri is None:
            return None
        # Return information about fmRI data file
        return FileInfo(
            fmri.upload_file,
            fmri.properties[datastore.PROPERTY_MIMETYPE],
            fmri.properties[datastore.PROPERTY_FILENAME]
        )