docs: def check_status_mapping(self):
          """ ensure status map does not contain status values which are not present in DB """
          self.verbose('checking status mapping...')
  
          if not self.status_mapping:
              self.message('no status mapping found')
              return
  
          for old_val, new_val in self.status_mapping.iteritems():
              try:
                  # look up by slug if new_val is string
                  if isinstance(new_val, basestring):
                      lookup = {'slug': new_val}
                  # lookup by primary key otherwise
                  else:
                      lookup = {'pk': new_val}
                  status = Status.objects.get(**lookup)
                  self.status_mapping[old_val] = status.id
              except Status.DoesNotExist:
                  raise ImproperlyConfigured('Error! Status with slug %s not found in the database' % new_val)
  
          self.verbose('status map correct')