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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_delete(self, experiment_id):
 """Delete fMRI data object associated with given experiment. Raises ValueError if an attempt is made to delete a read-only resource. Parameters experiment_id : string Unique experiment identifier Returns ------- FMRIDataHandle Handle for deleted data object or None if experiment is unknown or has no fMRI data object associated with it """

        # Get experiment fMRI to ensure that it exists
        fmri = self.experiments_fmri_get(experiment_id)
        if fmri is None:
            return None
        # Delete reference fMRI data object and set reference in experiment to
        # None. If the result of delete fMRI object is None we return None.
        # Alternatively, throw an exception to signal invalid database state.
        fmri = self.funcdata.delete_object(fmri.identifier)
        if not fmri is None:
            self.experiments.update_fmri_data(experiment_id, None)
        return funcdata.FMRIDataHandle(fmri, experiment_id)