libiconv.2.dylibのversionが古いというエラー解決法

##エラー
Pythonでcabochaを使いたかったため、importしてみた
ipythonにて

```
In [1]: import CaboCha
```
```
ImportError: dlopen(/anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so, 2): Library not loaded: @rpath/libiconv.2.dylib
  Referenced from: /anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so
  Reason: Incompatible library version: _CaboCha.cpython-36m-darwin.so requires version 8.0.0 or later, but libiconv.2.dylib provides version 7.0.0
```

共有ライブラリらへんでエラーがでているっぽい
ググってみたが
https://qiita.com/lapun/items/65039e59ac483c8dfd80


```
$ brew update
$ brew install libiconv
```
上のサイトのように試してみても変化なし
他にもportでupdateしようとしたが変化なし
##libiconv.2.dylibのversionの確認

```
$ otool -L /anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so
/anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so:
	/usr/local/lib/libcabocha.5.dylib (compatibility version 6.0.0, current version 6.0.0)
	/usr/local/lib/libcrfpp.0.dylib (compatibility version 1.0.0, current version 1.0.0)
	/usr/local/lib/libmecab.2.dylib (compatibility version 3.0.0, current version 3.0.0)
	/usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 104.1.0)
	@rpath/libiconv.2.dylib (compatibility version 8.0.0, current version 8.1.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1238.0.0)
```

libiconv.2.dylibのversionは```current version 8.1.0```なのでいいはず、、、
libiconv.2.dylibは```/usr/lib/libiconv.2.dylib```と```/opt/local/lib/libiconv.2.dylib```があるらしい
今は@rpathに```/usr/lib/```が入っており```/usr/lib/libiconv.2.dylib```が使われているよう

##それぞれのversion確認

```
$ otool -L /usr/lib/libiconv.2.dylib
/usr/lib/libiconv.2.dylib:
	/usr/lib/libiconv.2.dylib (compatibility version 7.0.0, current version 7.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1238.0.0)
```

```
$ otool -L /opt/local/lib/libiconv.2.dylib
/opt/local/lib/libiconv.2.dylib:
	/opt/local/lib/libiconv.2.dylib (compatibility version 9.0.0, current version 9.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1238.0.0)
```
見てみると```/opt/local/lib/libiconv.2.dylib```を使えば良さそう

##libiconv.2.dylibを置き換える

```
$ sudo install_name_tool -change "@rpath/libiconv.2.dylib"  "/opt/local/lib/libiconv.2.dylib" /anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so
```
参考：https://qiita.com/itoru257/items/d36b4e3908a39bfbbb18

すると

```
$ otool -L /anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so
/anaconda/lib/python3.6/site-packages/_CaboCha.cpython-36m-darwin.so:
	/usr/local/lib/libcabocha.5.dylib (compatibility version 6.0.0, current version 6.0.0)
	/usr/local/lib/libcrfpp.0.dylib (compatibility version 1.0.0, current version 1.0.0)
	/usr/local/lib/libmecab.2.dylib (compatibility version 3.0.0, current version 3.0.0)
	/usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 104.1.0)
	/opt/local/lib/libiconv.2.dylib (compatibility version 8.0.0, current version 8.1.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1238.0.0)
```
pathが置き換わっている(current versionは変わってない、、)のでimportしてみる

```
In [1]: import CaboCha

In [2]:
```

###importできた！
(/opt/local/lib/libiconv はmacportsでupgradeできるっぽいのだが、/usr/lib/libiconv.2.dylib のupgradeの方法がわからなかったので、前者に置き換えた感じ)