Pymongo inserts _id in original array after insert_many .how to avoid insertion of _id ? And why original array is updated with _id? Please explain  with example, if anybody knows? Thanks in advance.
Pymongo driver explicitly inserts _id of type ObjectId into the original array and hence original array gets updated before inserting into mongo. This is the expected behaviour of pymongo for insertmany query as per my previous experiences. Hope this answers your question.
Pymongo inserts _id in original array after insert_many .how to avoid insertion of _id?