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7th March 2022





  • New: Resolve the 409 error.

    Probably an exception was raised in the backend, use pdb to follow the trace and catch where it happened.

Python Snippets

  • New: How to Find Duplicates in a List in Python.

    numbers = [1, 2, 3, 2, 5, 3, 3, 5, 6, 3, 4, 5, 7]
    duplicates = [number for number in numbers if numbers.count(number) > 1]
    unique_duplicates = list(set(duplicates))

    If you want to count the number of occurrences of each duplicate, you can use:

    from collections import Counter
    numbers = [1, 2, 3, 2, 5, 3, 3, 5, 6, 3, 4, 5, 7]
    counts = dict(Counter(numbers))
    duplicates = {key:value for key, value in counts.items() if value > 1}

    To remove the duplicates use a combination of list and set:

    unique = list(set(numbers))
  • New: How to decompress a gz file.

    import gzip
    import shutil
    with'file.txt.gz', 'rb') as f_in:
        with open('file.txt', 'wb') as f_out:
            shutil.copyfileobj(f_in, f_out)
  • New: How to compress/decompress a tar file.

    def compress(tar_file, members):
        Adds files (`members`) to a tar_file and compress it
        tar =, mode="w:gz")
        for member in members:
    def decompress(tar_file, path, members=None):
        Extracts `tar_file` and puts the `members` to `path`.
        If members is None, all members on `tar_file` will be extracted.
        tar =, mode="r:gz")
        if members is None:
            members = tar.getmembers()
        for member in members:
            tar.extract(member, path=path)


Infrastructure Solutions


  • New: Introduce krew.

    Krew is a tool that makes it easy to use kubectl plugins. Krew helps you discover plugins, install and manage them on your machine. It is similar to tools like apt, dnf or brew.


  • New: Introduce Ksniff.

    Ksniff is a Kubectl plugin to ease sniffing on kubernetes pods using tcpdump and wireshark.


  • New: Introduce mizu.

    Mizu is an API Traffic Viewer for Kubernetes, think TCPDump and Chrome Dev Tools combined.


Operative Systems


Linux Snippets

  • Correction: Clean snap data.

    If you're using snap you can clean space by:

    • Reduce the number of versions kept of a package with snap set system refresh.retain=2
    • Remove the old versions with

      #Removes old revisions of snaps
      set -eu
      LANG=en_US.UTF-8 snap list --all | awk '/disabled/{print $1, $3}' |
          while read snapname revision; do
              snap remove "$snapname" --revision="$revision"
  • Correction: Clean journalctl data.

    • Check how much space it's using: journalctl --disk-usage
    • Rotate the logs: journalctl --rotate

    Then you have three ways to reduce the data:

    1. Clear journal log older than X days: journalctl --vacuum-time=2d
    2. Restrict logs to a certain size: journalctl --vacuum-size=100M
    3. Restrict number of log files: journactl --vacuum-files=5.

    The operations above will affect the logs you have right now, but it won't solve the problem in the future. To let journalctl know the space you want to use open the /etc/systemd/journald.conf file and set the SystemMaxUse to the amount you want (for example 1000M for a gigabyte). Once edited restart the service with sudo systemctl restart systemd-journald.

Last update: 2022-04-29