Failed install on Raspberry Pi

[yakir12]

I tried to add on a Raspberry Pi (headless Raspbian on 32-bit ARMv7) with Julia v1.7.2 and got the following error:

julia> using PythonCall
 │ Package PythonCall not found, but a package named PythonCall is available
 │ from a registry. 
 │ Install package?
 │   (dance) pkg> add PythonCall 
 └ (y/n) [y]: 
    Updating registry at `~/.julia/registries/General.toml`
   Resolving package versions...
   Installed UnsafePointers ─ v1.0.0
   Installed StructTypes ──── v1.8.1
   Installed CondaPkg ─────── v0.2.7
   Installed MicroMamba ───── v0.1.6
   Installed Scratch ──────── v1.1.0
   Installed JSON3 ────────── v1.9.2
   Installed PythonCall ───── v0.6.1
    Updating `~/dance/Project.toml`
  [6099a3de] + PythonCall v0.6.1
    Updating `~/dance/Manifest.toml`
  [992eb4ea] + CondaPkg v0.2.7
  [0f8b85d8] + JSON3 v1.9.2
  [1914dd2f] + MacroTools v0.5.9
  [0b3b1443] + MicroMamba v0.1.6
  [69de0a69] + Parsers v2.2.2
  [6099a3de] + PythonCall v0.6.1
  [6c6a2e73] + Scratch v1.1.0
  [856f2bd8] + StructTypes v1.8.1
  [e17b2a0c] + UnsafePointers v1.0.0
Precompiling project...
  8 dependencies successfully precompiled in 54 seconds (115 already precompiled)
    CondaPkg Found dependencies: /home/yakir/.julia/packages/PythonCall/Z6DIG/CondaPkg.toml
ERROR: InitError: Cannot locate artifact 'micromamba-0.21.0' in '/home/yakir/.julia/packages/MicroMamba/Ksju7/Artifacts.toml'
Stacktrace:
  [1] error(s::String)
    @ Base ./error.jl:33
  [2] ensure_artifact_installed(name::String, artifacts_toml::String; platform::Base.BinaryPlatforms.Platform, pkg_uuid::Nothing, verbose::Bool, quiet_download::Bool, io::Base.TTY)
    @ Pkg.Artifacts ~/julia-1.7.2/share/julia/stdlib/v1.7/Pkg/src/Artifacts.jl:401
  [3] executable(; io::IO)
    @ MicroMamba ~/.julia/packages/MicroMamba/Ksju7/src/MicroMamba.jl:37
  [4] cmd(; io::IO)
    @ MicroMamba ~/.julia/packages/MicroMamba/Ksju7/src/MicroMamba.jl:115
  [5] cmd(args::Any; io::IO)
    @ MicroMamba ~/.julia/packages/MicroMamba/Ksju7/src/MicroMamba.jl:119
  [6] conda_cmd(args::Any; io::IO)
    @ CondaPkg ~/.julia/packages/CondaPkg/GoPlj/src/backend.jl:38
  [7] _resolve_conda_create(io::Any, conda_env::Any, specs::Any, channels::Any)
    @ CondaPkg ~/.julia/packages/CondaPkg/GoPlj/src/resolve.jl:144
  [8] resolve(; force::Bool, io::IO, interactive::Bool, dry_run::Bool)
    @ CondaPkg ~/.julia/packages/CondaPkg/GoPlj/src/resolve.jl:261
  [9] resolve()
    @ CondaPkg ~/.julia/packages/CondaPkg/GoPlj/src/resolve.jl:209
 [10] envdir()
    @ CondaPkg ~/.julia/packages/CondaPkg/GoPlj/src/env.jl:66
 [11] init_context()
    @ PythonCall.C ~/.julia/packages/PythonCall/Z6DIG/src/cpython/context.jl:56
 [12] __init__()
    @ PythonCall.C ~/.julia/packages/PythonCall/Z6DIG/src/cpython/CPython.jl:21
 [13] _include_from_serialized(path::String, depmods::Vector{Any})
    @ Base ./loading.jl:768
 [14] _require_search_from_serialized(pkg::Base.PkgId, sourcepath::String)
    @ Base ./loading.jl:854
 [15] _require(pkg::Base.PkgId)
    @ Base ./loading.jl:1097
 [16] require(uuidkey::Base.PkgId)
    @ Base ./loading.jl:1013
 [17] require(into::Module, mod::Symbol)
    @ Base ./loading.jl:997
during initialization of module C

[cjdoris]

The error message isn't very clear, but means that MicroMamba does not support your platform. For now you'll need to install Conda or Mamba yourself and set the env var JULIA_CONDAPKG_BACKEND=System. Or install Python yourself and set JULIA_PYTHONCALL_EXE to its path.

[yakir12]

ENV["JULIA_PYTHONCALL_EXE"] = "/usr/bin/python3"

fixed it. Thank you!