IntervalValue does not accept integer or float about czml3

[astrojuanlu]

Hi @khoohuibo , thanks for your interest in czml3! I guess you refer to this piece of code:

czml3/src/czml3/types.py

Lines 318 to 335 in d7f0b72

	@attr.s(repr=False, frozen=True, kw_only=True)
	class IntervalValue(BaseCZMLObject):
	"""Value over some interval."""
	_start = attr.ib()
	_end = attr.ib()
	_value = attr.ib()
	def to_json(self):
	obj_dict = {"interval": TimeInterval(start=self._start, end=self._end)}
	try:
	obj_dict.update(**self._value.to_json())
	except AttributeError:
	key = TYPE_MAPPING[type(self._value)]
	obj_dict[key] = self._value
	return obj_dict

And here are a couple of examples of how to use IntervalValue from the tests:

czml3/tests/test_properties.py

Lines 540 to 543 in f0136f4

	start = dt.datetime(2019, 1, 1, tzinfo=dt.timezone.utc)
	end = dt.datetime(2019, 1, 2, tzinfo=dt.timezone.utc)
	prop = IntervalValue(start=start, end=end, value=True)

czml3/src/czml3/examples/simple.py

Lines 31 to 33 in d7f0b72

	clock=IntervalValue(
	start=start, end=end, value=Clock(currentTime=start, multiplier=60)
	),

Would you please paste here what code is producing the error you describe, so we can try to reproduce it? For my understanding everything is working as expected, but CZML documentation is sparse and it's also possible that I'm missing something.

[astrojuanlu]

Closing because of inactivity.