[SecurityFest2017] Empty [misc] [100pts]

This challenge was a 100 points challenge by Security Fest CTF 2017 :
Some suspicious character left this laying around on our system , seems to be empty.
Solves: 121
First I extracted the archive with the following command :
7z x empty.7z
Extracting the archive
Then, using strings command on the empty.pdf file, I found a string looking like a flag in hexadecimal :
/Widths[/Widths[83 67 84 70 123 115 116 114 52 110 103 51 95 111 98 106 51 99 116 95 99 104 114 95 49 110 95 112 108 52 49 110 95 115 49 116 51 125]
Now, I just had to decode the file from hex to character in python :
#!/usr/bin/env python

flagList = [83,67,84,70,123,115,116,114,52,110,103,51,95,111,98,106,51,99,116,95,99,104,114,95,49,110,95,112,108,52,49,110,95,115,49,116,51,125]

print("".join(chr(i) for i in flagList))
Decode the flag

Here’s the flag: SCTF{str4ng3_obj3ct_chr_1n_pl41n_s1t3} !

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