python - Traversing Django Foreign Keys efficiently for query sets -


i'm having trouble efficiently getting (second degree) related objects. models 

class transaction(models.model):   from_account = models.foreignkey(account, related_name="sent")   to_account = models.foreignkey(account, related_name="recieved")   ...  class account(models.model):   address = models.charfield(max_length=42, primary_key=true)   ...

what have been doing far aggregated list of transaced_with account follows:

accs = [] if hasattr(account, 'recieved'):     tx in account.recieved.all():         acc = tx.from_account         accs.append(acc)  if hasattr(account, 'sent'):     tx in account.sent.all():         acc = tx.to_account         accs.append(acc) return  accs

this way slow, wondering, the efficient way aggregate these sort of related objects? want in end list of address accounts in accs

prefetch_related friend here. documentation @ https://docs.djangoproject.com/en/1.11/ref/models/querysets/#prefetch-related


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