PyCall build on TravisCI fails

Out of sudden my the build of our Julia project on TravisCI https://travis-ci.org/JuliaEnergy/PowerDynamics.jl/builds/598602707 fails, due to PyCall:
```
┌ Error: Error building `PyCall`:
│ PREFIX=/home/travis/.julia/conda/3
│ Unpacking payload ...
Collecting package metadata (current_repodata.json): ...working... done
│ Solving environment: ...working... done
│
│ ## Package Plan ##
│
│ environment location: /home/travis/.julia/conda/3
│
│ added / updated specs:
│ - _libgcc_mutex==0.1=main
│ - asn1crypto==0.24.0=py37_0
│ - bzip2==1.0.8=h7b6447c_0
│ - ca-certificates==2019.5.15=0
│ - certifi==2019.6.16=py37_0
│ - cffi==1.12.3=py37h2e261b9_0
│ - chardet==3.0.4=py37_1
│ - conda-package-handling==1.3.11=py37_0
│ - conda==4.7.10=py37_0
│ - cryptography==2.7=py37h1ba5d50_0
│ - idna==2.8=py37_0
│ - libarchive==3.3.3=h5d8350f_5
│ - libedit==3.1.20181209=hc058e9b_0
│ - libffi==3.2.1=hd88cf55_4
│ - libgcc-ng==9.1.0=hdf63c60_0
│ - libstdcxx-ng==9.1.0=hdf63c60_0
│ - libxml2==2.9.9=hea5a465_1
│ - lz4-c==1.8.1.2=h14c3975_0
│ - lzo==2.10=h49e0be7_2
│ - ncurses==6.1=he6710b0_1
│ - openssl==1.1.1c=h7b6447c_1
│ - pip==19.1.1=py37_0
│ - pycosat==0.6.3=py37h14c3975_0
│ - pycparser==2.19=py37_0
│ - pyopenssl==19.0.0=py37_0
│ - pysocks==1.7.0=py37_0
│ - python-libarchive-c==2.8=py37_11
│ - python==3.7.3=h0371630_0
│ - readline==7.0=h7b6447c_5
│ - requests==2.22.0=py37_0
│ - ruamel_yaml==0.15.46=py37h14c3975_0
│ - setuptools==41.0.1=py37_0
│ - six==1.12.0=py37_0
│ - sqlite==3.29.0=h7b6447c_0
│ - tk==8.6.8=hbc83047_0
│ - tqdm==4.32.1=py_0
│ - urllib3==1.24.2=py37_0
│ - wheel==0.33.4=py37_0
│ - xz==5.2.4=h14c3975_4
│ - yaml==0.1.7=had09818_2
│ - zlib==1.2.11=h7b6447c_3
│ - zstd==1.3.7=h0b5b093_0
│
│
│ The following NEW packages will be INSTALLED:
│
│ _libgcc_mutex pkgs/main/linux-64::_libgcc_mutex-0.1-main
│ asn1crypto pkgs/main/linux-64::asn1crypto-0.24.0-py37_0
│ bzip2 pkgs/main/linux-64::bzip2-1.0.8-h7b6447c_0
│ ca-certificates pkgs/main/linux-64::ca-certificates-2019.5.15-0
│ certifi pkgs/main/linux-64::certifi-2019.6.16-py37_0
│ cffi pkgs/main/linux-64::cffi-1.12.3-py37h2e261b9_0
│ chardet pkgs/main/linux-64::chardet-3.0.4-py37_1
│ conda pkgs/main/linux-64::conda-4.7.10-py37_0
│ conda-package-han~ pkgs/main/linux-64::conda-package-handling-1.3.11-py37_0
│ cryptography pkgs/main/linux-64::cryptography-2.7-py37h1ba5d50_0
│ idna pkgs/main/linux-64::idna-2.8-py37_0
│ libarchive pkgs/main/linux-64::libarchive-3.3.3-h5d8350f_5
│ libedit pkgs/main/linux-64::libedit-3.1.20181209-hc058e9b_0
│ libffi pkgs/main/linux-64::libffi-3.2.1-hd88cf55_4
│ libgcc-ng pkgs/main/linux-64::libgcc-ng-9.1.0-hdf63c60_0
│ libstdcxx-ng pkgs/main/linux-64::libstdcxx-ng-9.1.0-hdf63c60_0
│ libxml2 pkgs/main/linux-64::libxml2-2.9.9-hea5a465_1
│ lz4-c pkgs/main/linux-64::lz4-c-1.8.1.2-h14c3975_0
│ lzo pkgs/main/linux-64::lzo-2.10-h49e0be7_2
│ ncurses pkgs/main/linux-64::ncurses-6.1-he6710b0_1
│ openssl pkgs/main/linux-64::openssl-1.1.1c-h7b6447c_1
│ pip pkgs/main/linux-64::pip-19.1.1-py37_0
│ pycosat pkgs/main/linux-64::pycosat-0.6.3-py37h14c3975_0
│ pycparser pkgs/main/linux-64::pycparser-2.19-py37_0
│ pyopenssl pkgs/main/linux-64::pyopenssl-19.0.0-py37_0
│ pysocks pkgs/main/linux-64::pysocks-1.7.0-py37_0
│ python pkgs/main/linux-64::python-3.7.3-h0371630_0
│ python-libarchive~ pkgs/main/linux-64::python-libarchive-c-2.8-py37_11
│ readline pkgs/main/linux-64::readline-7.0-h7b6447c_5
│ requests pkgs/main/linux-64::requests-2.22.0-py37_0
│ ruamel_yaml pkgs/main/linux-64::ruamel_yaml-0.15.46-py37h14c3975_0
│ setuptools pkgs/main/linux-64::setuptools-41.0.1-py37_0
│ six pkgs/main/linux-64::six-1.12.0-py37_0
│ sqlite pkgs/main/linux-64::sqlite-3.29.0-h7b6447c_0
│ tk pkgs/main/linux-64::tk-8.6.8-hbc83047_0
│ tqdm pkgs/main/noarch::tqdm-4.32.1-py_0
│ urllib3 pkgs/main/linux-64::urllib3-1.24.2-py37_0
│ wheel pkgs/main/linux-64::wheel-0.33.4-py37_0
│ xz pkgs/main/linux-64::xz-5.2.4-h14c3975_4
│ yaml pkgs/main/linux-64::yaml-0.1.7-had09818_2
│ zlib pkgs/main/linux-64::zlib-1.2.11-h7b6447c_3
│ zstd pkgs/main/linux-64::zstd-1.3.7-h0b5b093_0
│
│
│ Preparing transaction: ...working... done
│ Executing transaction: ...working... WARNING conda.core.envs_manager:register_env(46): Unable to register environment. Path not writable or missing.
│ environment location: /home/travis/.julia/conda/3
│ registry file: /home/travis/.conda/environments.txt
│ done
│ installation finished.
│ Warning: 'defaults' already in 'channels' list, moving to the top
│ Collecting package metadata (current_repodata.json): ...working... done
│ Solving environment: ...working... done
│
│ ## Package Plan ##
│
│ environment location: /home/travis/.julia/conda/3
│
│ added / updated specs:
│ - conda
│
│
│ The following packages will be downloaded:
│
│ package | build
│ ---------------------------|-----------------
│ asn1crypto-1.0.1 | py37_0 161 KB
│ ca-certificates-2019.8.28 | 0 132 KB
│ certifi-2019.9.11 | py37_0 154 KB
│ chardet-3.0.4 | py37_1003 174 KB
│ conda-4.7.12 | py37_0 3.0 MB
│ conda-package-handling-1.6.0| py37h7b6447c_0 797 KB
│ openssl-1.1.1d | h7b6447c_2 2.5 MB
│ pysocks-1.7.1 | py37_0 30 KB
│ sqlite-3.30.0 | h7b6447c_0 1.9 MB
│ tqdm-4.36.1 | py_0 50 KB
│ ------------------------------------------------------------
│ Total: 8.9 MB
│
│ The following packages will be REMOVED:
│
│ bzip2-1.0.8-h7b6447c_0
│ libarchive-3.3.3-h5d8350f_5
│ libxml2-2.9.9-hea5a465_1
│ lz4-c-1.8.1.2-h14c3975_0
│ lzo-2.10-h49e0be7_2
│ pip-19.1.1-py37_0
│ python-libarchive-c-2.8-py37_11
│ setuptools-41.0.1-py37_0
│ wheel-0.33.4-py37_0
│ zstd-1.3.7-h0b5b093_0
│
│ The following packages will be UPDATED:
│
│ asn1crypto 0.24.0-py37_0 --> 1.0.1-py37_0
│ ca-certificates 2019.5.15-0 --> 2019.8.28-0
│ certifi 2019.6.16-py37_0 --> 2019.9.11-py37_0
│ chardet 3.0.4-py37_1 --> 3.0.4-py37_1003
│ conda 4.7.10-py37_0 --> 4.7.12-py37_0
│ conda-package-han~ 1.3.11-py37_0 --> 1.6.0-py37h7b6447c_0
│ openssl 1.1.1c-h7b6447c_1 --> 1.1.1d-h7b6447c_2
│ pysocks 1.7.0-py37_0 --> 1.7.1-py37_0
│ sqlite 3.29.0-h7b6447c_0 --> 3.30.0-h7b6447c_0
│ tqdm 4.32.1-py_0 --> 4.36.1-py_0
│
│
│ Preparing transaction: ...working... done
│ Verifying transaction: ...working... failed
│
│ RemoveError: 'setuptools' is a dependency of conda and cannot be removed from
│ conda's operating environment.
│
│ ┌ Info: No system-wide Python was found; got the following error:
│ │ Base.IOError("could not spawn setenv(`conda -c \"import distutils.sysconfig; print(distutils.sysconfig.get_config_var('VERSION'))\"`,[\"TRAVIS_OSX_IMAGE=\", \"DOCUMENTER_KEY=[secure]\", \"PATH=/home/travis/bin:/home/travis/.local/bin:/usr/local/lib/jvm/openjdk11/bin:/opt/pyenv/shims:/home/travis/.phpenv/shims:/home/travis/perl5/perlbrew/bin:/home/travis/.nvm/versions/node/v8.12.0/bin:/home/travis/.kiex/elixirs/elixir-1.7.4/bin:/home/travis/.kiex/bin:/home/travis/.rvm/gems/ruby-2.5.3/bin:/home/travis/.rvm/gems/ruby-2.5.3@global/bin:/home/travis/.rvm/rubies/ruby-2.5.3/bin:/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.11.1.linux.amd64/bin:/usr/local/cmake-3.12.4/bin:/usr/local/clang-7.0.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/opt/ghc/bin:/home/travis/.rvm/bin:/home/travis/.phpenv/bin:/opt/pyenv/bin:/home/travis/.yarn/bin:/home/travis/julia/bin:/home/travis/julia/bin\", \"_system_version=16.04\", \"TRAVIS_CABAL_DEFAULT=2.4\", \"TRAVIS_BRANCH=master\", \"OPENBLAS_MAIN_FREE=1\", \"TRAVIS_UID=2000\", \"TRAVIS_SUDO=true\", \"TRAVIS_ALLOW_FAILURE=false\", \"COMPOSER_NO_INTERACTION=1\", \"TRAVIS_TMPDIR=/tmp/tmp.OWjSFrXy1Y\", \"TRAVIS_JOB_NUMBER=459.1\", \"TRAVIS_PULL_REQUEST_SHA=\", \"TRAVIS_TIMER_ID=00ccac56\", \"TRAVIS_INIT=systemd\", \"MANPATH=/home/travis/.nvm/versions/node/v8.12.0/share/man:/home/travis/.kiex/elixirs/elixir-1.7.4/man:/home/travis/.rvm/rubies/ruby-2.5.3/share/man:/usr/local/cmake-3.12.4/man:/usr/local/clang-7.0.0/share/man:/usr/local/man:/usr/local/share/man:/usr/share/man:/home/travis/.rvm/man\", \"TRAVIS_BUILD_ID=598602707\", \"TRAVIS_PULL_REQUEST_SLUG=\", \"TRAVIS_SECURE_ENV_VARS=true\", \"MYSQL_UNIX_PORT=/var/run/mysqld/mysqld.sock\", \"TRAVIS_BUILD_NUMBER=459\", \"PYENV_ROOT=/opt/pyenv\", \"NVM_CD_FLAGS=\", \"ANSI_CLEAR=\\\\033[0K\", \"CONTINUOUS_INTEGRATION=true\", \"TRAVIS_TEST_RESULT=\", \"TRAVIS_BUILD_STAGE_NAME=\", \"RAILS_ENV=test\", \"TRAVIS_INTERNAL_RUBY_REGEX=^ruby-(2\\\\.[0-4]\\\\.[0-9]|1\\\\.9\\\\.3)\", \"MIX_ARCHIVES=/home/travis/.kiex/mix/elixir-1.7.4\", \"ANSI_GREEN=\\\\033[32;1m\", \"USER=travis\", \"PS4=+\", \"TRAVIS_STACK_FEATURES=basic couchdb disabled-ipv6 docker docker-compose elasticsearch firefox go-toolchain google-chrome jdk memcached mongodb mysql nodejs_interpreter perl_interpreter perlbrew phantomjs postgresql python_interpreter redis ruby_interpreter sqlite xserver\", \"GOPATH=/home/travis/gopath\", \"rvm_version=1.29.7 (latest)\", \"ELIXIR_VERSION=1.7.4\", \"JAVA_HOME=/usr/local/lib/jvm/openjdk11\", \"JRUBY_OPTS= --client -J-XX:+TieredCompilation -J-XX:TieredStopAtLevel=1 -J-Xss2m -Xcompile.invokedynamic=false\", \"TRAVIS_JULIA_VERSION=1.2\", \"APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=1\", \"TRAVIS_PULL_REQUEST=false\", \"TRAVIS_TIMER_START_TIME=1571224778665885138\", \"XDG_DATA_DIRS=/usr/local/share:/usr/share:/var/lib/snapd/desktop\", \"TRAVIS_PULL_REQUEST_BRANCH=\", \"TRAVIS_JOB_ID=598602708\", \"SHELL=/bin/bash\", \"TRAVIS_TAG=\", \"HISTFILESIZE=2000\", \"TRAVIS_ROOT=/\", \"RUBY_VERSION=ruby-2.5.3\", \"RACK_ENV=test\", \"PYTHON_CONFIGURE_OPTS=--enable-unicode=ucs4 --with-wide-unicode --enable-shared --enable-ipv6 --enable-loadable-sqlite-extensions --with-computed-gotos\", \"PYTHON_CFLAGS=-g -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security\", \"NVM_DIR=/home/travis/.nvm\", \"PS1=\\\${debian_chroot:+(\\\$debian_chroot)}\\\\u@\\\\h:\\\\w\\\\\\\$ \", \"NVM_BIN=/home/travis/.nvm/versions/node/v8.12.0/bin\", \"DEBIAN_FRONTEND=noninteractive\", \"SSH_CLIENT=10.24.6.19 40144 22\", \"TRAVIS_STACK_TIMESTAMP=2019-03-25 16:16:39 UTC\", \"SSH_TTY=/dev/pts/0\", \"DOCUMENTER_DEBUG=true\", \"TERM=xterm\", \"HOME=/home/travis\", \"PYTHONIOENCODING=UTF-8\", \"PYTHON=conda\", \"TRAVIS_APP_HOST=build.travis-ci.org\", \"HISTSIZE=1000\", \"rvm_path=/home/travis/.rvm\", \"TRAVIS_OS_NAME=linux\", \"TRAVIS_ENABLE_INFRA_DETECTION=true\", \"HAS_ANTARES_THREE_LITTLE_FRONZIES_BADGE=true\", \"LC_ALL=en_US.UTF-8\", \"rvm_prefix=/home/travis\", \"LC_CTYPE=en_US.UTF-8\", \"PERLBREW_SHELLRC_VERSION=0.86\", \"TZ=UTC\", \"_system_type=Linux\", \"GIT_ASKPASS=echo\", \"TRAVIS_ARCH=amd64\", \"LANG=en_US.UTF-8\", \"PYENV_SHELL=bash\", \"SHLVL=2\", \"LOGNAME=travis\", \"TRAVIS_FILTERED=redirect_io\", \"XDG_RUNTIME_DIR=/run/user/2000\", \"rvm_bin_path=/home/travis/.rvm/bin\", \"TRAVIS_APT_PROXY=http://apt.cache.travis-ci.com\", \"OLDPWD=/home/travis/build\", \"IRBRC=/home/travis/.rvm/rubies/ruby-2.5.3/.irbrc\", \"TRAVIS_REPO_SLUG=JuliaEnergy/PowerDynamics.jl\", \"RBENV_SHELL=bash\", \"GEM_PATH=/home/travis/.rvm/gems/ruby-2.5.3:/home/travis/.rvm/gems/ruby-2.5.3@global\", \"PAGER=cat\", \"TRAVIS_COMMIT=334ee88d39fe13c8da9293634b2f42d6b5b64984\", \"TRAVIS_STACK_NODE_ATTRIBUTES=/.node-attributes.yml\", \"TRAVIS_COMMIT_RANGE=50c5117adb06e196b32af18e6dbfa4520484ce50...334ee88d39fe13c8da9293634b2f42d6b5b64984\", \"ANSI_RED=\\\\033[31;1m\", \"_=/home/travis/julia/bin/julia\", \"ANSI_RESET=\\\\033[0m\", \"PERLBREW_HOME=/home/travis/.perlbrew\", \"PERLBREW_ROOT=/home/travis/perl5/perlbrew\", \"TRAVIS_PRE_CHEF_BOOTSTRAP_TIME=2019-03-25T16:16:25\", \"PWD=/home/travis/build/JuliaEnergy/PowerDynamics.jl\", \"TRAVIS_EVENT_TYPE=cron\", \"TRAVIS_GHC_DEFAULT=8.6.1\", \"TRAVIS_STACK_NAME=opal\", \"TRAVIS_GHC_ROOT=/opt/ghc\", \"MERB_ENV=test\", \"SSH_CONNECTION=10.24.6.19 40144 10.20.0.68 22\", \"LANGUAGE=en_US.UTF-8\", \"MY_RUBY_HOME=/home/travis/.rvm/rubies/ruby-2.5.3\", \"TRAVIS_COMMIT_MESSAGE=function added for finding valid conditions for perturbed systems wit… (#54)\\n\\n* function added for finding valid conditions for perturbed systems with mass matrices\\r\\n\\r\\n* removed commented code\\r\\n\\r\\n* ODEFunction taken from OrdinaryDiffEquations package\\r\", \"CI=true\", \"TRAVIS_CMD=julia --check-bounds=yes --color=yes --inline=no -e \\\"using Pkg; Pkg.test(coverage=true)\\\" && julia -e 'using Pkg; Pkg.add(\\\"Coverage\\\"); using Coverage; res=Codecov.process_folder(); Codecov.submit(res);'\", \"HISTCONTROL=ignoredups:ignorespace\", \"MAIL=/var/mail/travis\", \"GEM_HOME=/home/travis/.rvm/gems/ruby-2.5.3\", \"TRAVIS_STACK_JOB_BOARD_REGISTER=/.job-board-register.yml\", \"TRAVIS_BUILD_WEB_URL=https://travis-ci.org/JuliaEnergy/PowerDynamics.jl/builds/598602707\", \"XDG_SESSION_ID=2\", \"TRAVIS_STACK_LANGUAGES=__opal__ crystal csharp d dart elixir erlang haskell haxe julia perl perl6 r rust\", \"TRAVIS_INFRA=unknown\", \"TRAVIS_LANGUAGE=julia\", \"TRAVIS_JOB_WEB_URL=https://travis-ci.org/JuliaEnergy/PowerDynamics.jl/jobs/598602708\", \"_system_arch=x86_64\", \"TRAVIS_HOME=/home/travis\", \"TRAVIS_BUILD_DIR=/home/travis/build/JuliaEnergy/PowerDynamics.jl\", \"JULIA_LOAD_PATH=@:/tmp/jl_ONLJvI\", \"TRAVIS_JOB_NAME=\", \"TRAVIS=true\", \"ANSI_YELLOW=\\\\033[33;1m\", \"TRAVIS_CABAL_ROOT=/opt/cabal\", \"HAS_JOSH_K_SEAL_OF_APPROVAL=true\", \"_system_name=Ubuntu\", \"TRAVIS_DIST=xenial\", \"GOROOT=/home/travis/.gimme/versions/go1.11.1.linux.amd64\"]): no such file or directory (ENOENT)", -2)
│ └ using the Python distribution in the Conda package
│ [ Info: Downloading miniconda installer ...
│ [ Info: Installing miniconda ...
│ [ Info: Running `conda config --add channels defaults --file /home/travis/.julia/conda/3/condarc-julia.yml --force` in root environment
│ [ Info: Running `conda update -q -y conda` in root environment
│ ERROR: LoadError: failed process: Process(setenv(`/home/travis/.julia/conda/3/bin/conda update -q -y conda`,["TRAVIS_OSX_IMAGE=", "DOCUMENTER_KEY=[secure]", "PATH=/home/travis/bin:/home/travis/.local/bin:/usr/local/lib/jvm/openjdk11/bin:/opt/pyenv/shims:/home/travis/.phpenv/shims:/home/travis/perl5/perlbrew/bin:/home/travis/.nvm/versions/node/v8.12.0/bin:/home/travis/.kiex/elixirs/elixir-1.7.4/bin:/home/travis/.kiex/bin:/home/travis/.rvm/gems/ruby-2.5.3/bin:/home/travis/.rvm/gems/ruby-2.5.3@global/bin:/home/travis/.rvm/rubies/ruby-2.5.3/bin:/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.11.1.linux.amd64/bin:/usr/local/cmake-3.12.4/bin:/usr/local/clang-7.0.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/opt/ghc/bin:/home/travis/.rvm/bin:/home/travis/.phpenv/bin:/opt/pyenv/bin:/home/travis/.yarn/bin:/home/travis/julia/bin:/home/travis/julia/bin", "_system_version=16.04", "TRAVIS_CABAL_DEFAULT=2.4", "TRAVIS_BRANCH=master", "OPENBLAS_MAIN_FREE=1", "TRAVIS_UID=2000", "TRAVIS_SUDO=true", "TRAVIS_ALLOW_FAILURE=false" … "TRAVIS_BUILD_DIR=/home/travis/build/JuliaEnergy/PowerDynamics.jl", "JULIA_LOAD_PATH=@:/tmp/jl_ONLJvI", "TRAVIS_JOB_NAME=", "TRAVIS=true", "ANSI_YELLOW=\\033[33;1m", "TRAVIS_CABAL_ROOT=/opt/cabal", "HAS_JOSH_K_SEAL_OF_APPROVAL=true", "_system_name=Ubuntu", "TRAVIS_DIST=xenial", "GOROOT=/home/travis/.gimme/versions/go1.11.1.linux.amd64"]), ProcessExited(1)) [1]
│
│ Stacktrace:
│ [1] pipeline_error at ./process.jl:813 [inlined]
│ [2] #run#536(::Bool, ::typeof(run), ::Cmd) at ./process.jl:728
│ [3] run(::Cmd) at ./process.jl:726
│ [4] runconda(::Cmd, ::String) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:113
│ [5] runconda(::Cmd) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:111
│ [6] _install_conda(::String, ::Bool) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:172
│ [7] _install_conda(::String) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:152
│ [8] runconda(::Cmd, ::String) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:111
│ [9] #add#1(::String, ::typeof(Conda.add), ::String, ::String) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:184
│ [10] add(::String, ::String) at /home/travis/.julia/packages/Conda/kLXeC/src/Conda.jl:183 (repeats 2 times)
│ [11] top-level scope at /home/travis/.julia/packages/PyCall/ttONZ/deps/build.jl:84
│ [12] include at ./boot.jl:328 [inlined]
│ [13] include_relative(::Module, ::String) at ./loading.jl:1094
│ [14] include(::Module, ::String) at ./Base.jl:31
│ [15] include(::String) at ./client.jl:431
│ [16] top-level scope at none:5
│ in expression starting at /home/travis/.julia/packages/PyCall/ttONZ/deps/build.jl:43
└ @ Pkg.Operations /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.2/Pkg/src/backwards_compatible_isolation.jl:647
ERROR: LoadError: LoadError: PyCall not properly installed. Please run Pkg.build("PyCall")
```

Start with the linked TravisCI build 598602707 and the PyCall installation log, focusing on the Conda RemoveError involving setuptools. Reproduce the Julia 1.2 TravisCI build if the project configuration is available. Done means PyCall builds successfully and the project’s CI run completes without this error.

Scritto dal modello di indicizzazione a partire dal testo della issue.