Used protoc 3.12.3 (latest).
Solves many DeprecationWarnings, e.g.:
...\electrum\paymentrequest_pb2.py:114: DeprecationWarning: Call to deprecated create function FieldDescriptor(). Note: Create unlinked descriptors is going to go away. Please use get/find descriptors from generated code or query the descriptor_pool.
_descriptor.FieldDescriptor(
...\electrum\paymentrequest_pb2.py:65: DeprecationWarning: Call to deprecated create function Descriptor(). Note: Create unlinked descriptors is going to go away. Please use get/find descriptors from generated code or query the descriptor_pool.