Hi guix! I want to output the deps of a package to
a writable file. Like say the "hello" world
package, I'd like to insert a file after, say the
install phase, so that later I could parse it and
serve it from a website. Here's a snip of what I
have:

#+begin_src scheme
(add-after 'install 'create-dependency-file
                 (lambda* (#:key inputs outputs #:allow-other-keys)
                   (call-with-output-file
                       (string-append
                        (assoc-ref outputs "out")
                        "/lib/python3.8/site-packages"
                        "/wqflask/DEPENDENCIES.txt")
                     (lambda (port)
                       (format
                        port "
#### System Inputs (generated from Guix)
|Name | Version | Home Page | Description |
|-----|---------|-----------|-------------|
|~a|
"
                        (apply
                         string-append
                         (map (lambda (input)
                                (let ((name (car input)))
                                  (string-append
                                   "| **" name "** | "
                                   ,(package-version
                                     (specification->package name)) " | "
                                   ,(package-home-page
                                     (specification->package name))
                                   " |"
                                   ,(package-description
                                     (specification->package name))
                                   " |\n")))
                              inputs)))
                       ))
                   ))
#+end_src

That ^^ doesn't seem to work as I'd like it to. The output(truncated)
looks something like:
                            
#+begin_src markdown
➜  guix git:(master) ✗ cat ~/opt/python3-genenetwork2/lib/python3.8/site-packages/wqflask/DEPENDENCIES.txt


 #### System Inputs (generated from Guix)
|Name | Version | Home Page | Description |
|-----|---------|-----------|-------------|
|| **python** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **source** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-colorbox** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **coreutils** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **git** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **which** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **grep** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **r** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **r-ctl** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **r-qtl** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **r-wgcna** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **redis** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **mariadb** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **gemma** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **gemma-wrapper** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **plink-ng-gn** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **racket-minimal** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **rust-qtlreaper** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **nginx** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **python-twint** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **python-unittest2** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-twitter-post-fetcher** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-cytoscape** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-panzoom** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-qtip** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-chroma** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-d3-tip** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-jscolor** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-colorbox** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-jszip** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **js-jstat** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **js-md5** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **js-parsley** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-plotly** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-typeahead** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **js-underscore** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **js-smart-time-ago** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
| **javascript-nouislider** | 3.11-guix-84cbf35 | http://genenetwork.org/ |Genenetwork installation sumo. |
#+end_src

Notice that the version, home page and description
are repeated across rows. Herein lies my question:
How would you fetch the details of the inputs(like
version, home-page, description) etc etc from a
modifed phase. Do I need to create a closure from
which I can import the modules like say _(use (gnu
packages))_. How do I do that if that's the case?

Is it also possible to get the same information in
a fine grained manner, like say get the
propagated-inputs instead of getting /all/ inputs?

-- 
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