require error: unable to find a version of 'composite_primary_keys' to activate

[yichaulin]

Hello,

I set the mysql.rb file to anonymize. However, it raise some errors as following.
The error raised at the require 'data-anonymization'.
I tried to gem install composite_primary_keys, but the error is still raised.
Do I have any mistake to using this gem?

/Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:113:in `require': unable to find a version of 'composite_primary_keys' to activate (Gem::LoadError)
        from /Users/Max/.rvm/gems/ruby-2.3.3/gems/data-anonymization-0.8.1/lib/utils/database.rb:2:in `<top (required)>'
        from /Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:68:in `require'
        from /Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:68:in `require'
        from /Users/Max/.rvm/gems/ruby-2.3.3/gems/data-anonymization-0.8.1/lib/data-anonymization.rb:20:in `<top (required)>'
        from /Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:133:in `require'
        from /Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:133:in `rescue in require'
        from /Users/Max/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:40:in `require'
        from mysql.rb:1:in `<main>'