配列の末尾に0を補完したい　ValueError: I/O operation on closed file.

前提

{'batch_label': 'testing batch 1 of 1', 
'labels':[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2], 'data':
array([[-440,-910,-1501,-1667,-1346,-781,94,779,1057,1622,2082,1609,462,-606,-1421,-1912,-2019,-1861,-1541,-1092,-290,796,1637,1909,1817,1633,1298,778,691,1062,-558,-1786,-777,-365,-227,94,162,-292,-795,-763,-437,-166,346,1051,1398,1131,425,-178,-400,-303,-134,-103,-88,-93,19,149,79,-167,-457,-650,-657,-694,-818,-496,146,690,1173,1349,1102,849,453,-124,-497,-745,-1021,-1081,-874,-648,-411,-42,277,395,423,477,521,588,664,433,42,-317,-702,-948,-1159,-1256,-104,636,-708,-1624,-197,1851,2316,2202,1568,202,-603,-1227,-2074,-2626,-2338,-1039,686,2215,2962,2861,2246,1284,435,-357,-1207,-1724,-1767,-1270,-496,63,222,430,759,600,19,-605,-1323,-1955,-1420,-472,-1549,-1381,0],[-470,-387,-200,35,186,226,89,-155,-337,-573,-910,-738,1155,1120,-1110,-886,778,2213,2542,1043,-260,-413,-477,-466,-594,-980,-1235,-1070,-685,-313,58,402,745,986,1067,1055,881,458,-123,-519,-635,-601,-462,-276,-93,-15,-74,75,407,685,797,591,278,74,-45,72,199,-194,-750,-891,-518,-35,-41,543,1255,-988,-3550,-1998,1368,2219,1315,962,780,237,-811,-1884,-2128,-1266,223,1310,1348,758,207,112,305,321,-60,-542,-859,-938,-788,-690,-472,146,851,1183,1046,814,664,196,-223,49,879,34,-885,-282,69,205,-29,-303,-589,-735,-496,-272,-280,-252,-70,107,83,-26,71,195,291,598,755,509,136,-213,-504,-607,-430,-105,117,33,-180,-227,0],...
...,367,363,0,0,0,0,0,0,0,0,0,0,0,0]]),
'filename':['.csv',' .csv',' .csv',' .csv',' ...]}

このような形の辞書型リストを作成しています。

実現したいこと

ここで私がやりたいことは、'data'というラベルにたくさんの数字配列が格納されているのですが、それぞれの末尾に0を647個ずつ補完したいと思っています。
プログラムの34行目以降になりますが、以下のようなエラーが出て作成ができません。
どのようにデバックすれば良いでしょうか。
よろしくお願いいたします。

発生している問題・エラーメッセージ

ValueError                                Traceback (most recent call last)
<ipython-input-12-ce07c8472c1c> in <module>
      4 data2 = [np.pad(data, ((0, 0), (0, 647)))]
      5 print(data2)
----> 6 f.write("'data':array(")
      7 
      8 for row in data2:

ValueError: I/O operation on closed file.

該当のソースコード

python
1import pandas as pd
2import numpy as np
3
4f = open('output.txt', 'w')
5
6df = pd.read_csv('test_125.csv')
7
8all_files = list(df.columns.values)
9
10files = []
11for i in range(0, len(all_files), 3):
12    files.append(all_files[i])
13
14f.write("{'filename':[")
15files2 = ",".join(files)
16for i in files:
17    f.write("'")
18    f.write(i)
19    f.write("'")
20    if i != files[-1]:
21        f.write(",")
22f.write("], ")
23
24df2 = df[files]
25array = df2.values
26label = array[-1].tolist()
27label = [str(int(x)) for x in label]
28
29f.write("'label':[")
30label2 = ",".join(label)
31f.writelines(label2)
32f.write("], ")
33
34array_t = np.array(array).T
35data = [[str(int(k)) for k in l[:-1]] for l in array_t]
36data2 = [np.pad(data, ((0, 0), (0, 647)))]  #######←
37print(data2)
38f.write("'data':array(")
39
40for row in data2:
41    f.write("[")
42    row2 = ",".join(row)
43    f.write(row2)
44    f.write("]")
45    if row != data2[-1]:
46        f.write(",")
47f.write(")}")
48
49f.close()
50