code: def requires_list(self):
          
          requires = self.variant.get_requires(build_requires=self.building)
          reqlist = RequirementList(requires)
  
          if reqlist.conflict:
              raise ResolveError(
                  "The package %s has an internal requirements conflict: %s"
                  % (str(self), str(reqlist)))
  
          return reqlist
docs: It is important that this property is calculated lazily. Getting the
          'requires' attribute may trigger a package load, which may be avoided if
          this variant is reduced away before that happens.