How to strip 2nd value from list of tuples while keeping the sublist structure intact?-CodePudding

I have a list of tuples within a list of lists. I want to strip the second value from each tuple while keeping the sublist structure intact. I have tried a for loop where I pull the first value, but that collapses the structure of the sublist into just a single list of every word.

The code I have is:

tokenz = [word_tokenize(i) for i in data_file]
tokenz = [l[:2] for l in tokenz]
tuples = [tuple(x) for x in tokenz]
tuples = [list(g) for k, g in groupby(tuples, key=bool) if k]

tuples

Right now my output is:

[('EU', 'NNP'),
  ('rejects', 'VBZ'),
  ('German', 'JJ'),
  ('call', 'NN'),
  ('to', 'TO'),
  ('boycott', 'VB'),
  ('British', 'JJ'),
  ('lamb', 'NN'),
  ('.', '.')],
 [('Peter', 'NNP'), ('Blackburn', 'NNP')],
 [('BRUSSELS', 'NNP'), ('1996-08-22', 'CD')],

I am trying to get it to look like this:

['EU', 'rejects', 'German', 'call', 'to', 'boycott', 'British', 'lamb', '.'],
['Peter', 'Blackburn'],
['BRUSSELS', '1996-08-22']

CodePudding user response：

Use nested list comprehensions

tuples = [
     [('EU', 'NNP'),
      ('rejects', 'VBZ'),
      ('German', 'JJ'),
      ('call', 'NN'),
      ('to', 'TO'),
      ('boycott', 'VB'),
      ('British', 'JJ'),
      ('lamb', 'NN'),
      ('.', '.')],
     [('Peter', 'NNP'), ('Blackburn', 'NNP')],
     [('BRUSSELS', 'NNP'), ('1996-08-22', 'CD')]
    ]

result = [[tup[0] for tup in list_of_tuples] for list_of_tuples in tuples]