Question

I just beginning to program in Python. I have read in some records from a text file into lists where the fourth item in the record is a long string which sometimes spans multiple lines. For example,

[ *, *, *, TXT1]
[TXT2]
[TXT3]
[ *, *, *, TXT4]
[TXT5]
[ *, *, *, TXT6]
[ *, *, *, TXT7]

How can I create a new list of lists from the original such that it correctly shows

[ *, *, *, TXT1+TXT2+TXT3]
[ *, *, *, TXT4+TXT5]
[ *, *, *, TXT6]
[ *, *, *, TXT7]

Answer 1

Assuming you have a list of lists here called linelist that looks like [[*,*,*,TXT1],[TXT2],[TXT3],[*,*,*,TXT4],...]:

newoutput = []
for item in linelist:
   if len(item) == 1:
       newoutput[-1][-1] += item[0]
   else:
       newoutput.append(item)

At the end, your output will be like:

[
    [*,*,*,TXT1+TXT2+TXT3],
    ...
]

In use:

>>> a
[['.', '.', '.', 'a'], ['b'], ['c'], ['.', '.', '.', 'd'], ['.', '.', '.', 'e']]

>>> newoutput = []
>>> for item in a:
...   if len(item) == 1:
...     newoutput[-1][-1] += item[0]
...   else:
...     newoutput.append(item)
...
>>> newoutput
[['.', '.', '.', 'abc'], ['.', '.', '.', 'd'], ['.', '.', '.', 'e']]
>>>