def parse_encode_biosample(data):
    """Parse a python dictionary containing
    ENCODE's biosample metadata into a dictionary 
    with select biosample metadata
    
    :param data: python dictionary containing ENCODE' biosample metadata
    :type s: dict

    :return: dictionary with parsed ENCODE's biosample metadata
    :rtype: dict
    """
    keys_biosample = ['accession', 'dbxrefs', 'description', 'genetic_modifications', 'treatments', 'sex', 'life_stage', 'age', 'age_units', 'organism', 'genetic_modifications' ]
    biosample = {key: data.get(key, '') for key in keys_biosample}

    keys_biosample_ontology = ['classification', 'term_name', 'organ_slims', 'cell_slims', 'system_slims', 'developmental_slims', 'system_slims', 'treatments', 'genetic_modifications']
    biosample_ontology = {key: data.get(key, '') for key in keys_biosample_ontology}
    biosample.update({'biosample_ontology': biosample_ontology})
    return biosample