Removing Certain Numbers From File

[chascp]

Hey Everyone,

I have a data file full of various numbers e.g.

1 2 3 1 180
2 3 4 1 180
3 4 5 1 180
4 5 6 1 180
5 6 7 1 180
6 7 8 1 180
7 8 9 1 180
8 9 10 1 180
9 10 11 1 180
10 11 12 1 180
12 13 14 1 180
11 12 13 1 180
15 16 17 1 180
14 15 16 1 180
13 14 15 1 180
18 19 20 1 180
17 18 19 1 180
16 17 18 1 180
1000
2 3 4 1 154.251
1 2 3 1 158.186
3 4 5 1 174.914
4 5 6 1 178.98
5 6 7 1 173.529
6 7 8 1 170.674
7 8 9 1 167.303
8 9 10 1 171.968
9 10 11 1 166.438
11 12 13 1 167.12
10 11 12 1 173.609
12 13 14 1 169.945
15 16 17 1 163.017
14 15 16 1 169.985
13 14 15 1 168.141
18 19 20 1 135.138
17 18 19 1 175.661
16 17 18 1 163.794
2000
1 2 3 1 170.264
2 3 4 1 176.227
3 4 5 1 153.696
4 5 6 1 107.968
5 6 7 1 133.734
6 7 8 1 173.96
7 8 9 1 158.41
8 9 10 1 168.659
9 10 11 1 168.945
11 12 13 1 162.38
10 11 12 1 172.85
12 13 14 1 163.664
13 14 15 1 138.511
16 17 18 1 106.912
15 16 17 1 149.535
14 15 16 1 149.883
18 19 20 1 117.114
17 18 19 1 127.023
3000
1 2 3 1 119.887
2 3 4 1 110.368
3 4 5 1 115.445
4 5 6 1 170.901
5 6 7 1 155.545
etc,

As you can see I also have multiple of 1000 in here and this goes on up to 1000000. I want to know if anyone can help me with trying to write a python script that can remove the multiples of 1000 from this text file.
At the moment i've tried the code below but it just produces an empty output file.

infile1 = 'angles1.txt'
outfile1 = 'angles_out.txt'
fin1 = open(infile1)
fout1 = open(outfile1, 'w+')

def filter_by_multiple(seq, n):
for i in seq:
if i % n:
yield i

filter_by_multiple(fout1, 1000)
list(filter_by_multiple(fout1, 1000))

fout1.write(''.join(list(filter_by_multiple(fout1, 1000))))
fin1.close()
fout1.close()

Thanks in advance!