mapping values are not allowed in this context at line 115 column 10

/opt/vagrant/embedded/lib/ruby/2.4.0/psych.rb:377:in `parse‘: (<unknown>): mapping values are not allowed in this context at line 115 column 10 (Psych::SyntaxError)
from /opt/vagrant/embedded/lib/ruby/2.4.0/psych.rb:377:in `parse_stream‘
from /opt/vagrant/embedded/lib/ruby/2.4.0/psych.rb:325:in `parse‘
from /opt/vagrant/embedded/lib/ruby/2.4.0/psych.rb:252:in `load‘
from /Users/qudian/Homestead/Vagrantfile:28:in `block in <top (required)>‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/v2/loader.rb:37:in `load‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/loader.rb:126:in `block (2 levels) in load‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/loader.rb:119:in `each‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/loader.rb:119:in `block in load‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/loader.rb:116:in `each‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/config/loader.rb:116:in `load‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/vagrantfile.rb:28:in `initialize‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:777:in `new‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:777:in `vagrantfile‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:523:in `host‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:191:in `block in action_runner‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/action/runner.rb:33:in `run‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:510:in `hook‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/lib/vagrant/environment.rb:759:in `unload‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/bin/vagrant:164:in `ensure in <main>‘
from /opt/vagrant/embedded/gems/2.1.2/gems/vagrant-2.1.2/bin/vagrant:164:in `<main>‘