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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 text2class_txt_iterator(source_txt_path, label_txt_path, class_strs=None):
 """Yield dicts for Text2ClassProblem.generate_samples from lines of files. Args: source_txt_path: txt file with record per line. label_txt_path: txt file with label per line, either as int or str. If string, must provide class_strs. class_strs: list<str> of class label names. Must be in correct order (i.e. ["a", "b", "c"] means that "a" will get class ID 0, "b" ID 1, etc.). Yields: {"inputs": inputs, "label": label} """

  if class_strs:
    class_strs = dict([(s, i) for i, s in enumerate(class_strs)])
  for inputs, label in zip(
      txt_line_iterator(source_txt_path), txt_line_iterator(label_txt_path)):
    label = label.strip()
    if class_strs:
      label = class_strs[label]
    else:
      label = int(label)
    yield {"inputs": inputs, "label": label}