[MacPorts] #59900: Install of youtube-dl requires multiple Python modules of various versions

[MacPorts]

#59900: Install of youtube-dl requires multiple Python modules of various versions
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 Reporter:  spmundi   |      Owner:  (none)
     Type:  defect    |     Status:  new
 Priority:  Normal    |  Milestone:
Component:  ports     |    Version:  2.6.2
 Keywords:  variants  |       Port:
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 I am running MacPorts 2.6.2
 I have python36 installed and selected.

 I want to install youtube-dl.
 The install is asking me you install python27, python38 and various
 python37 modules. Here is a list:
 ffmpeg
 gdk-pixbuf2
 gobject-introspection
 graphviz
 ld64
 ld64-xcode
 libLASi
 librsvg
 nasm
 pango
 py37-beaker
 py37-mako
 py37-markdown
 py37-markupsafe
 py37-setuptools
 python27
 python37
 python38
 vala
 I do not understand how the dependencies can be requiring versions of
 Python that, even if installed, would not be the active versions.
 Evidently the sub-Portfiles of youtube-dl, aren specifying
 dependencies on these python versions. But why? Should not that depency be
 merely on python and not a specific version of python?

 It does no good for me to try and install using variants. EG port install
 youtube-dl -python38. There is no difference in the output. I do not wish
 to have me ports cluttered up with all manner of pythonx.x installs which
 I am not using.

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Ticket URL: <https://trac.macports.org/ticket/59900>
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