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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 parse_na_line(txt: str, units: Units) -> typing.Dict[str, str]: """ Parser for the North American TAF forcast varient """

    retwx = {}
    wxdata = txt.split(' ')
    wxdata, _, retwx['wind_shear'] = core.sanitize_report_list(wxdata)
    wxdata, retwx['type'], retwx['start_time'], retwx['end_time'] = core.get_type_and_times(wxdata)
    wxdata, retwx['wind_direction'], retwx['wind_speed'], \
        retwx['wind_gust'], _ = core.get_wind(wxdata, units)
    wxdata, retwx['visibility'] = core.get_visibility(wxdata, units)
    wxdata, retwx['clouds'] = core.get_clouds(wxdata)
    retwx['other'], retwx['altimeter'], retwx['icing'], retwx['turbulance'] \
        = core.get_taf_alt_ice_turb(wxdata)
    return retwx