Add Keep A Tally With collections.Counter as a Python TIL

README.md

@@ -10,7 +10,7 @@ working across different projects via [VisualMode](https://www.visualmode.dev/).
 
 For a steady stream of TILs, [sign up for my newsletter](https://visualmode.kit.com/newsletter).
 
-_1743 TILs and counting..._
+_1745 TILs and counting..._
 
 See some of the other learning resources I work on:
 
@@ -1039,6 +1039,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Dunder Methods](python/dunder-methods.md)
 - [Install With PIP For Specific Interpreter](python/install-with-pip-for-specific-interpreter.md)
 - [Iterate First N Items From Enumerable](python/iterate-first-n-items-from-enumerable.md)
+- [Keep A Tally With collections.Counter](python/keep-a-tally-with-collections-counter.md)
 - [Load A File Into The Python REPL](python/load-a-file-into-the-python-repl.md)
 - [Override The Boolean Context Of A Class](python/override-the-boolean-context-of-a-class.md)
 - [Store And Access Immutable Data In A Tuple](python/store-and-access-immutable-data-in-a-tuple.md)
@@ -1710,6 +1711,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Ignore A Directory During ripgrep Search](unix/ignore-a-directory-during-ripgrep-search.md)
 - [Ignore The Alias When Running A Command](unix/ignore-the-alias-when-running-a-command.md)
 - [Include Ignore Files In Ripgrep Search](unix/include-ignore-files-in-ripgrep-search.md)
+- [Inspect EXIF Data For An Image File](unix/inspect-exif-data-for-an-image-file.md)
 - [Interactively Browse Available Node Versions](unix/interactively-browse-availabile-node-versions.md)
 - [Interactively Switch asdf Package Versions](unix/interactively-switch-asdf-package-versions.md)
 - [Interpret Cron Schedule From The CLI](unix/interpret-cron-schedule-from-the-cli.md)

python/keep-a-tally-with-collections-counter.md

@@ -0,0 +1,40 @@
+# Keep A Tally With collections.Counter
+
+Python's `collections` module comes with a
+[`Counter`](https://docs.python.org/3/library/collections.html#collections.Counter)
+object which is a specialized dict subclass focussed on tallying counts of keys.
+
+> It is a collection where elements are stored as dictionary keys and their
+> counts are stored as dictionary values. Counts are allowed to be any integer
+> value including zero or negative counts.
+
+I used it recently while doing an exploratory implementation of a Byte-Pair
+Encoding (BPE):
+
+```python
+from collections import Counter
+
+def get_pair_counts(token_ids: list[int]) -> Counter:
+    """Count how often each adjacent pair appears"""
+    counts = Counter()
+    for i in range(len(token_ids) - 1):
+        pair = (token_ids[i], token_ids[i + 1])
+        counts[pair] += 1
+    return counts
+```
+
+Here I'm able to count the number of occurrences of each pair of bytes from the
+input text. A tuple of `int` values is hashable, so they work great as keys for
+a `Counter`.
+
+The count value of any key will default to `0`. That makes it straightforward to
+increment from there as you iterating over occurrences.
+
+```python
+>>> counts = Counter()
+>>> counts['hello']
+0
+>>> count['hello'] += 1
+>>> count['hello']
+1
+```

unix/inspect-exif-data-for-an-image-file.md

@@ -0,0 +1,47 @@
+# Inspect EXIF Data For An Image File
+
+The `exiftool` CLI (which can be downloaded via `brew`) is a useful tool for
+inspecting all the EXIF data attached to a media file. A media file like an
+image has a bunch of additional details embedded in it like timestamps, image
+metadata, and sometimes location information.
+
+Here is all the data attached to a screenshot I found on my desktop:
+
+```bash
+❯ exiftool ~/Desktop/CleanShot\ 2025-11-17\ at\ 11.22.18@2x.png
+ExifTool Version Number         : 13.50
+File Name                       : CleanShot 2025-11-17 at 11.22.18@2x.png
+Directory                       : /Users/lastword/Desktop
+File Size                       : 1194 kB
+File Modification Date/Time     : 2025:11:17 11:22:21-06:00
+File Access Date/Time           : 2025:12:15 10:43:55-06:00
+File Inode Change Date/Time     : 2025:12:05 15:37:48-06:00
+File Permissions                : -rw-r--r--
+File Type                       : PNG
+File Type Extension             : png
+MIME Type                       : image/png
+Image Width                     : 2502
+Image Height                    : 1232
+Bit Depth                       : 8
+Color Type                      : RGB with Alpha
+Compression                     : Deflate/Inflate
+Filter                          : Adaptive
+Interlace                       : Noninterlaced
+XMP Toolkit                     : XMP Core 6.0.0
+Y Resolution                    : 144
+Resolution Unit                 : inches
+X Resolution                    : 144
+Exif Image Width                : 2502
+Color Space                     : sRGB
+User Comment                    : Screenshot
+Exif Image Height               : 1232
+SRGB Rendering                  : Perceptual
+Image Size                      : 2502x1232
+Megapixels                      : 3.1
+```
+
+This works with other kinds of media files. For instance, I ran this against an
+MP4 screen recording file which contained even more metadata.
+
+In addition to reading data, `exiftool` can also write it. See `man exiftool`
+for more details on what else it can do.