Invalid delayed_option on SegmentNotification

[evaldez89]

client = OneSignal(app_id, api_key)
notification_to_all_users = SegmentNotification(
    headings={
        "es": "Hello From Python"
    },
    contents={
        "en": "Python OneSignal Push Notification"
    },
    included_segments=["Test Users"]
)
response = client.send(notification_to_all_users)
details = client.details(notification_to_all_users)

print(response)

Result:

Traceback (most recent call last):
  File "openapi.py", line 20, in <module>
    response = client.send(notification_to_all_users)
  File "/home/user/.pyenv/versions/3.8.1/lib/python3.8/site-packages/onesignal/core.py", line 77, in send
    response = self.request("post", "notifications", json=data)
  File "/home/user/.pyenv/versions/3.8.1/lib/python3.8/site-packages/onesignal/core.py", line 48, in request
    raise OneSignalAPIError(r.json())
onesignal.errors.OneSignalAPIError: {'errors': ['invalid delayed_option'], 'success': False}

Expected Result:

print(response)
# {'id': '6xxxxxc7-5fxxx-4sxx-bea8-02f728xxxx02', 'recipients': 1, 'external_id': None}
print(response.status_code)
# 200 (OK)