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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 row_to_geojson(row, lon, lat, precision, date_format='epoch'):
 """Convert a pandas dataframe row to a geojson format object. Converts all datetimes to epoch seconds. """


    # Let pandas handle json serialization
    row_json = json.loads(row.to_json(date_format=date_format, date_unit='s'))
    return geojson.Feature(geometry=geojson.Point((round(row_json[lon], precision), round(row_json[lat], precision))),
                           properties={key: row_json[key] for key in row_json.keys() if key not in [lon, lat]})