我使用命令sudo gem uninstall cocoapods卸载了cocoapods。稍后我使用命令sudo gem install cocoapods进行安装，错误如下所示
Error installing cocoapods:
ERROR: Failed to build gem native extension.
current directory: /Library/Ruby/Gems/2.3.0/gems/json-2.1.0/ext/json/ext/generator
/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby -I /Library/Ruby/Site/2.3.0 -r ./siteconf20190929-29689-1blhfxj.rb extconf.rb
Ignoring bigdecimal-1.3.5 because its extensions are not built. Try: gem pristine bigdecimal --version 1.3.5
Ignoring bigdecimal-1.3.4 because its extensions are not built. Try: gem pristine bigdecimal --version 1.3.4
Ignoring bigdecimal-1.3.2 because its extensions are not built. Try: gem pristine bigdecimal --version 1.3.2
mkmf.rb can't find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/include/ruby.h
extconf failed, exit code 1
您知道该如何解决吗？