code: def target(self, project_module):
          
          assert isinstance(project_module, basestring)
          if project_module not in self.module2target:
              self.module2target[project_module] = \
                  b2.build.targets.ProjectTarget(project_module, project_module,
                                self.attribute(project_module, "requirements"))
  
          return self.module2target[project_module]
docs: Returns the project target corresponding to the 'project-module'.