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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 get_protein_targets_only(target_chembl_ids):
 """Given list of ChEMBL target ids, return dict of SINGLE PROTEIN targets Parameters target_chembl_ids : list list of chembl_ids as strings Returns ------- protein_targets : dict dictionary keyed to ChEMBL target ids with lists of activity ids """

    protein_targets = {}
    for target_chembl_id in target_chembl_ids:
        target = query_target(target_chembl_id)
        if 'SINGLE PROTEIN' in target['target_type']:
            protein_targets[target_chembl_id] = target
    return protein_targets