+ def get_all_floats_or_nones(self, key: str) -> list[float | None]:
+ """Retrieve list of float value at key, None if empty strings."""
+ ret: list[float | None] = []
+ for val in self.get_all_str(key):
+ if '' == val:
+ ret += [None]
+ else:
+ try:
+ ret += [float(val)]
+ except ValueError as e:
+ msg = f'cannot float form field value for key {key}: {val}'
+ raise BadFormatException(msg) from e
+ return ret
+