blockchain.get_all_accounts(): suppress duplicates

Fixes holgern#27

beem/blockchain.py

@@ -581,6 +581,7 @@ def get_all_accounts(self, start='', stop='', steps=1e3, limit=-1, **kwargs):
             :param int steps: Obtain ``steps`` ret with a single call from RPC
         """
         lastname = start
+        skipname = ''
         cnt = 1
         if not self.steem.is_connected():
             raise OfflineHasNoRPCException("No RPC available in offline mode!")
@@ -591,10 +592,15 @@ def get_all_accounts(self, start='', stop='', steps=1e3, limit=-1, **kwargs):
             else:
                 ret = self.steem.rpc.lookup_accounts(lastname, steps)
             for account in ret:
+                # skip the first result of this call if it's identical to the
+                # last result of the previous call
+                if account == skipname:
+                    continue
                 yield account
                 cnt += 1
                 if account == stop or (limit > 0 and cnt > limit):
                     raise StopIteration
+            skipname = ret[-1]
             if lastname == ret[-1]:
                 raise StopIteration
             lastname = ret[-1]