Check if ExtractiveResources is missing in template

[kaerumy]

Traceback (innermost last):
  Module ZPublisher.WSGIPublisher, line 162, in transaction_pubevents
  Module ZPublisher.WSGIPublisher, line 371, in publish_module
  Module ZPublisher.WSGIPublisher, line 274, in publish
  Module ZPublisher.mapply, line 85, in mapply
  Module ZPublisher.WSGIPublisher, line 63, in call_object
  Module politikus.extractives.views.extractives_view, line 18, in __call__
  Module plone.autoform.view, line 42, in __call__
  Module plone.autoform.view, line 33, in render
  Module Products.Five.browser.pagetemplatefile, line 126, in __call__
  Module Products.Five.browser.pagetemplatefile, line 61, in __call__
  Module zope.pagetemplate.pagetemplate, line 135, in pt_render
  Module Products.PageTemplates.engine, line 378, in __call__
  Module z3c.pt.pagetemplate, line 176, in render
  Module chameleon.zpt.template, line 302, in render
  Module chameleon.template, line 214, in render
  Module chameleon.template, line 192, in render
  Module 6aac398f8ab08668c2544cdbe4b36177, line 1916, in render
  Module 7f895ef8a504d09e4b2f8950d9e71037, line 1255, in render_master
  Module 7f895ef8a504d09e4b2f8950d9e71037, line 430, in render_content
  Module 6aac398f8ab08668c2544cdbe4b36177, line 1901, in __fill_main
  Module 6aac398f8ab08668c2544cdbe4b36177, line 365, in render_main
  Module zope.tales.expressions, line 250, in __call__
  Module Products.PageTemplates.Expressions, line 188, in _eval
  Module zope.tales.expressions, line 153, in _eval
  Module Products.PageTemplates.Expressions, line 102, in trustedBoboAwareZopeTraverse
  Module OFS.Traversable, line 343, in unrestrictedTraverse
   - __traceback_info__: ([], 'ExtractiveResources')
KeyError: 'ExtractiveResources'

 - Expression: "context/ExtractiveResources"
 - Filename:   ... ives/src/politikus/extractives/views/extractives_view.pt
 - Location:   (line 27: col 34)
 - Source:     ... l:repeat="resources context/ExtractiveResources">
                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 - Expression: "context/main_template/macros/master"
 - Filename:   ... ives/src/politikus/extractives/views/extractives_view.pt
 - Location:   (line 6: col 23)
 - Source:     ... etal:use-macro="context/main_template/macros/master">
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 - Arguments:  repeat: <Products.PageTemplates.engine.RepeatDictWrapper object at 0x7f41273ceeb0>
               template: <Products.Five.browser.pagetemplatefile.ViewPageTemplateFile object at 0x7f412ea5fdd0>
               views: <Products.Five.browser.pagetemplatefile.ViewMapper object at 0x7f412e30d6d0>
               request: <WSGIRequest, URL=https://politikus.sinarproject.org/extractives/manganese-and-other-minerals-mining-operation-on-lot-89798/extractives-view>
               args: ()
               here: <ExtractiveConcession at /politikus/extractives/manganese-and-other-minerals-mining-operation-on-lot-89798>
               user: <PloneUser 'kaeru'>
               nothing: None
               root: <Application at >
               translate: <function translate at 0x7f412dfdf3d0>
               container: <ExtractiveConcession at /politikus/extractives/manganese-and-other-minerals-mining-operation-on-lot-89798>
               modules: <Products.PageTemplates.ZRPythonExpr._SecureModuleImporter object at 0x7f4153372b10>
               traverse_subpath: []
               default: <DEFAULT>
               loop: {}
               context: <ExtractiveConcession at /politikus/extractives/manganese-and-other-minerals-mining-operation-on-lot-89798>
               view: <Products.Five.browser.metaconfigure.SimpleViewClass from /var/plone/politikus-sinar/src/politikus.extractives/src/politikus/extractives/views/extractives_view.pt object at 0x7f412e7a3950>
               target_language: None
               macroname: u'master'
               options: {}
               attrs: {}