bundle init
Generates a Gemfile into the current working directory
$ bundle init [--gemspec=FILE]
Options:
--gemspec: Use the specified .gemspec to create the Gemfile
Init generates a default Gemfile in the current working directory. When
adding a Gemfile to a gem with a gemspec, the --gemspec option will
automatically add each dependency listed in the gemspec file to the newly
created Gemfile.
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