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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 latlon_to_grid(latlon):
    '''convert to grid reference'''
    from MAVProxy.modules.lib.ANUGA import redfearn
    (zone, easting, northing) = redfearn.redfearn(latlon[0], latlon[1])
    if latlon[0] < 0:
        hemisphere = 'S'
    else:
        hemisphere = 'N'
    return UTMGrid(zone, easting, northing, hemisphere=hemisphere)