def METHOD_NAME(fl):
    """
    Subsets the flow list for all HAP emissions based on list of flows from
    EPA.
    :param fl: df in standard flowlist format
    :return: df in standard flowlist format
    """
    flows = fl[fl["Context"].str.startswith("emission/air")]
    haps = pd.read_csv(inputpath / 'HAP_flows.csv', usecols=['Flowable'])
    # HAPs sourced from EPA via script write_HAP_flows.py
    # https://www.epa.gov/haps/initial-list-hazardous-air-pollutants-modifications
    flows = flows[flows['Flowable'].isin(haps.Flowable)]
    return flows