For the above - here is what the structure looks like when you query it without the where:
{'entities': [{'id': '/Milestone/36pn82tc0qjx507kncuo7jfa11130', 'Name': 'Executing and Monitoring & Controlling', 'StartDate': '2019-01-31T13:00:00.0000000', 'DueDate': '2019-01-31T21:00:00.0000000', 'Work': {'unit': 'Hours', 'value': 8.0}, 'ActualEffort': {'unit': 'Hours', 'value': 8.0}, 'ParentProject': {'id': '/Project/36pn82tc0qjx507kncuo7jfa11109'}}
so I am trying to add the where so I can filter it by the parentproject id
Note, I also tried this sytax and did not get a result:
{'typeName': 'Milestone',
'fields': ['Name', 'StartDate', 'DueDate', 'Work', 'ActualEffort', 'ParentProject'],
'where': {'and': [{
'leftExpression': {'fieldName': 'ParentProject'},
'operator': 'Equal',
'rightExpression': {"value": '{id: /Project/36pn82tc0qjx507kncuo7jfa11109}'}
}]}
}