title: ZipImportError while toolchain build python3 for kivy-ios programming
body: <p>Trying to re-install the kivy-ios environment for iOS application, but &quot;python3 toolchain.py build python3&quot; gives me following ZipImportError error.
  I learned that, /usr/include folder is gone due to Apple's new strategy from Big Sur, so tried many things on the web like,</p>
  <ol>
  <li>CommandlineTools re-installation<br />
  sudo rm -rf /Library/Developer/CommandLineTools<br />
  xcode-select --install</li>
  <li>zlib installation and environment variable setting for zlib<br />
  brew install zlib<br />
  export LDFLAGS=&quot;-L/usr/local/opt/zlib/lib&quot;<br />
  export CPPFLAGS=&quot;-I/usr/local/opt/zlib/include&quot;</li>
  <li>X-code CommandlineTools selection<br />
  XCode-&gt;Preference-&gt;Locations-&gt;CommandlineTools</li>
  <li>SDK environment variable setting<br />
  export SDKROOT=&quot;$(xcrun --sdk macosx --show-sdk-path)&quot;</li>
  <li>build/link environment variable setting<br />
  export LDFLAGS=&quot;-L$(xcrun --show-sdk-path)/usr/lib&quot;<br />
  export CFLAGS=&quot;-I$(xcrun --show-sdk-path)/usr/include&quot;</li>
  </ol>
  <p>, but none of them works and still give me zipimport.ZipImportError. Any advice would be appreciated!</p>
  <ul>
  <li>Error message</li>
  </ul>
  <pre><code>[DEBUG   ] Traceback (most recent call last):
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/runpy.py&quot;, line 193, in _run_module_as_main
  [DEBUG   ]     &quot;__main__&quot;, mod_spec)
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/runpy.py&quot;, line 85, in _run_code
  [DEBUG   ]     exec(code, run_globals)
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/ensurepip/__main__.py&quot;, line 5, in &lt;module&gt;
  [DEBUG   ]     sys.exit(ensurepip._main())
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/ensurepip/__init__.py&quot;, line 204, in _main
  [DEBUG   ]     default_pip=args.default_pip,
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/ensurepip/__init__.py&quot;, line 117, in _bootstrap
  [DEBUG   ]     return _run_pip(args + [p[0] for p in _PROJECTS], additional_paths)
  [DEBUG   ]   File &quot;/Users/taka/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Lib/ensurepip/__init__.py&quot;, line 27, in _run_pip
  [DEBUG   ]     import pip._internal
  [DEBUG   ] zipimport.ZipImportError: can't decompress data; zlib not available
  [DEBUG   ] make: *** [install] Error 1
  Exception in thread background thread for pid 17598:
  Traceback (most recent call last):
    File &quot;/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py&quot;, line 917, in _bootstrap_inner
      self.run()
    File &quot;/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/threading.py&quot;, line 865, in run
      self._target(*self._args, **self._kwargs)
    File &quot;/Users/taka/venv/py37/lib/python3.7/site-packages/sh.py&quot;, line 1540, in wrap
      fn(*args, **kwargs)
    File &quot;/Users/taka/venv/py37/lib/python3.7/site-packages/sh.py&quot;, line 2459, in background_thread
      handle_exit_code(exit_code)
    File &quot;/Users/taka/venv/py37/lib/python3.7/site-packages/sh.py&quot;, line 2157, in fn
      return self.command.handle_command_exit_code(exit_code)
    File &quot;/Users/taka/venv/py37/lib/python3.7/site-packages/sh.py&quot;, line 815, in handle_command_exit_code
      raise exc
  sh.ErrorReturnCode_2: 
  </code></pre>
  <ul>
  <li>Environment
  MacOS: Big Sur 11.6<br />
  Python: 3.7.1<br />
  kivy-ios: 1.2.1<br />
  kivy: 1.11.1<br />
  Dependency: autoconf automake libtool pkg-config glib openssl@1.1  autogen zlib freetype ...</li>
  </ul>