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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 formal_cities(reverse=False):
 """ Get a dictionary that maps all Backpage city names to their presentable, formal names. Returns: dictionary of Backpage city names mapped to formal city names """

  output = {}
  fname = pkg_resources.resource_filename(__name__, 'resources/Formal_City_Name_Pairs.csv')
  with open(fname, 'rU') as csvfile:
    reader = csv.reader(csvfile, delimiter = ',')
    for row in reader:
      if not reverse:
        # Informal to formal
        output[row[0]] = row[1]
      else:
        # Formal to informal
        output[row[1]] = row[0]
  return output