Why python script doesn't print to console or can't debug using pdb in Ubuntu

[nyanmn]

I am looking into the code.

For training lpr, we can use train.py in lpr folder.

train.py uses methods and classes in trainer.py, such as CTCUtils, InputData, inference and LPRVocab.

I put print inside LPRVocab to see how the code works as follows.

class LPRVocab:
  @staticmethod
  def create_vocab(train_list_path, val_list_path, use_h_concat=False, use_oi_concat=False):
    print('create_vocab called ')
    [vocab, r_vocab, num_classes] = LPRVocab._create_standard_vocabs(train_list_path, val_list_path)
    if use_h_concat:
      [vocab, r_vocab, num_classes] = LPRVocab._concat_all_hieroglyphs(vocab, r_vocab)
    if use_oi_concat:
      [vocab, r_vocab, num_classes] = LPRVocab._concat_oi(vocab, r_vocab)

    return vocab, r_vocab, num_classes

  @staticmethod
  def _char_range(char1, char2):
    """Generates the characters from `char1` to `char2`, inclusive."""
    for char_code in range(ord(char1), ord(char2) + 1):
      yield chr(char_code)

  # Function for reading special symbols
  @staticmethod
  def _read_specials(filepath):
    characters = set()
    with open(filepath, 'r') as file_:
      for line in file_:
        current_label = line.split(' ')[-1].strip()
        characters = characters.union(re.findall('(<[^>]*>|.)', current_label))
    return characters

  @staticmethod
  def _create_standard_vocabs(train_list_path, val_list_path):
    print('_create_standard_vocabs called ')
    chars = set().union(LPRVocab._char_range('A', 'Z')).union(LPRVocab._char_range('0', '9'))
    print(chars)
    print('for special characters')
    chars = chars.union(LPRVocab._read_specials(train_list_path)).union(LPRVocab._read_specials(val_list_path))
    print(chars)
    print('for list characters')
    chars = list(chars)
    print(chars)
    print('for sort characters')
    chars.sort()
    print(chars)
    print('for append characters')
    chars.append('_')
    print(chars)    
    num_classes = len(chars)
    print('num_classes '+str(num_classes))
    vocab = dict(zip(chars, range(num_classes)))
    print('vocab ')
    print(vocab)
    r_vocab = dict(zip(range(num_classes), chars))
    r_vocab[-1] = ''
    print('r_vocab ')
    print(r_vocab)
    return [vocab, r_vocab, num_classes]

But I don't see any prints to console.

Then I used

python -m pdb train.py

then set break point inside trainer.py. Break points are never hit. Press Key S also doesn't make to go detail inside another files.

Why debug desn't work and print doesn't print to console? I used python3.5.