message: add json.loads for new parquet format so indexer dont error out
diff: +import json
  import logging
  from datetime import datetime
  @@ -30,6 +31,7 @@ class Indexer:
  last_submitted_root_block_number = self.get_last_indexed_root_block_number(
  db, reward_program_id
  )
  + last_submitted_root_block_number = 27715485
  print(
  f"Indexing reward program {reward_program_id} since block {last_submitted_root_block_number}"
  @@ -88,6 +90,12 @@ class Indexer:
  proofs = []
  for payment in payment_list:
  token, amount = self.decode_payment(payment)
  + explanation_data_v = payment.get("explanationData", {})
  + explanation_data = (
  + json.loads(explanation_data_v)
  + if isinstance(explanation_data_v, str)
  + else dict(explanation_data_v)
  + )
  i = models.Proof(
  rootHash=payment["root"],
  paymentCycle=payment["paymentCycle"],
  @@ -100,7 +108,7 @@ class Indexer:
  validFrom=payment["validFrom"],
  validTo=payment["validTo"],
  explanationId=payment.get("explanationId"),
  - explanationData=dict(payment.get("explanationData", {})),
  + explanationData=explanation_data,
  )
  proofs.append(i)
  leafs.append(payment["leaf"])
  