$ heroku run “ruby -rpsych -e ”p Psych.libyaml_version.join(‘.’)”” -a <app name>

<internal:lib/rubygems/custom_require>:29:in `require': no such file to load -- psych (LoadError)
  from <internal:lib/rubygems/custom_require>:29:in `require'

-bash: syntax error near unexpected token `('

$ heroku run “ruby -rpsych -e ”p Psych.libyaml_version.join(‘.’)”” -a <app name>