zipimport.ZipImportError: can't decompress data; zlib not availableの対処

## pyenvで最新版の3.7.0を入れようとしたところタイトルのエラーがでた

### 実行コマンド
```
pyenv install 3.7.0
```

### エラー詳細
```
python-build: use openssl from homebrew
python-build: use readline from homebrew
Downloading Python-3.7.0.tar.xz...
-> https://www.python.org/ftp/python/3.7.0/Python-3.7.0.tar.xz
Installing Python-3.7.0...
python-build: use readline from homebrew

BUILD FAILED (OS X 10.13.5 using python-build 1.2.6)

Inspect or clean up the working tree at /var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197
Results logged to /var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197.log

Last 10 log lines:
  File "/private/var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197/Python-3.7.0/Lib/ensurepip/__main__.py", line 5, in <module>
    sys.exit(ensurepip._main())
  File "/private/var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197/Python-3.7.0/Lib/ensurepip/__init__.py", line 204, in _main
    default_pip=args.default_pip,
  File "/private/var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197/Python-3.7.0/Lib/ensurepip/__init__.py", line 117, in _bootstrap
    return _run_pip(args + [p[0] for p in _PROJECTS], additional_paths)
  File "/private/var/folders/81/sn1mnk7s46j9l0r4gbb2q_6s076m6k/T/python-build.20180719181130.73197/Python-3.7.0/Lib/ensurepip/__init__.py", line 27, in _run_pip
    import pip._internal
zipimport.ZipImportError: can't decompress data; zlib not available
make: *** [install] Error 1
```

### 解決策
```
xcode-select --install
```

完了してから、再インストールしたら成功。

## 3.7.0を入れた後に3.6.6を入れようとしたら同様のエラーが発生

### 解決策

```
$ brew info zlib

zlib: stable 1.2.11 (bottled) [keg-only]
General-purpose lossless data-compression library
https://zlib.net/
/usr/local/Cellar/zlib/1.2.11 (12 files, 373KB)
  Poured from bottle on 2019-01-16 at 16:52:44
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/zlib.rb
==> Caveats
zlib is keg-only, which means it was not symlinked into /usr/local,
because macOS already provides this software and installing another version in
parallel can cause all kinds of trouble.

For compilers to find zlib you may need to set:
  export LDFLAGS="-L/usr/local/opt/zlib/lib"
  export CPPFLAGS="-I/usr/local/opt/zlib/include"

For pkg-config to find zlib you may need to set:
  export PKG_CONFIG_PATH="/usr/local/opt/zlib/lib/pkgconfig"

==> Analytics
install: 9,036 (30 days), 29,291 (90 days), 74,561 (365 days)
install_on_request: 7,818 (30 days), 25,042 (90 days), 60,748 (365 days)
build_error: 0 (30 days)
```

表示されたexportを実行

それぞれの環境変数の設定を行った後、installすると成功した
```
$ export LDFLAGS="-L/usr/local/opt/zlib/lib"
$ export CPPFLAGS="-I/usr/local/opt/zlib/include"
$ export PKG_CONFIG_PATH="/usr/local/opt/zlib/lib/pkgconfig"
```

Python3.6.6のインストール
```
$ pyenv install 3.6.6
python-build: use openssl from homebrew
python-build: use readline from homebrew
Downloading Python-3.6.6.tar.xz...
-> https://www.python.org/ftp/python/3.6.6/Python-3.6.6.tar.xz
Installing Python-3.6.6...
python-build: use readline from homebrew
Installed Python-3.6.6 to /Users/xxxxx/.anyenv/envs/pyenv/versions/3.6.6
```

## 参考
[Install failed, "zlib not available" on macOS Mojave](https://github.com/pyenv/pyenv/issues/1219#issuecomment-448658430)