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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 make_shp_filename(place_name):
 """ Create a filename string in a consistent format from a place name string. Parameters place_name : string place name to convert into a filename Returns ------- string """

    name_pieces = list(reversed(place_name.split(', ')))
    filename = '-'.join(name_pieces).lower().replace(' ','_')
    filename = re.sub('[^0-9a-zA-Z_-]+', '', filename)
    return filename