docs: def to_envvars(self):
          """
          Export property values to a dictionary with environment variable names as keys.
          """
          export = {}
          for prop_name in self.profile_properties:
              prop = self._get_prop(prop_name)
              value = self[prop_name]
              if value is not None:
                  export[prop.get_envvar(self)] = prop.to_str(self, value)
          if self._profile_parent_name:
              export[
                  f"{self._envvar_prefix}PARENT_PROFILE".upper()
              ] = self._profile_parent_name
          return export