【commandnotfound:pod】cocoapos出错

pod update

/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/psych.rb:205:in `parse': (): could not find expected ':' while scanning a simple key at line 11 column 1 (Psych::SyntaxError)

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/psych.rb:205:in `parse_stream'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/psych.rb:153:in `parse'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/psych.rb:129:in `load'

from /Library/Ruby/Site/2.0.0/rubygems/config_file.rb:333:in `load_file'

from /Library/Ruby/Site/2.0.0/rubygems/config_file.rb:198:in `initialize'

from /Library/Ruby/Site/2.0.0/rubygems/gem_runner.rb:74:in `new'

from /Library/Ruby/Site/2.0.0/rubygems/gem_runner.rb:74:in `do_configuration'

from /Library/Ruby/Site/2.0.0/rubygems/gem_runner.rb:39:in `run'

from /usr/bin/gem:21:in `

'

 gem uninstall cocoapods

gem sources -l

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