fixes from review for readability

torba/baseaccount.py

@@ -111,13 +111,7 @@ class HierarchicalDeterministic(AddressManager):
         keys_batch, final_keys = [], []
         for index in range(start, end+1):
             keys_batch.append((index, self.public_key.child(index)))
-            if len(keys_batch) % 180 == 0:
-                yield self.db.add_keys(
-                    self.account, self.chain_number, keys_batch
-                )
-                final_keys.extend(keys_batch)
-                keys_batch.clear()
-        if keys_batch:
+            if index % 180 == 0 or index == end:
                 yield self.db.add_keys(
                     self.account, self.chain_number, keys_batch
                 )

torba/basedatabase.py

@@ -169,6 +169,10 @@ class SQLiteMixin:
 
 class BaseDatabase(SQLiteMixin):
 
+    PRAGMAS = """
+        pragma journal_mode=WAL;
+    """
+
     CREATE_PUBKEY_ADDRESS_TABLE = """
         create table if not exists pubkey_address (
             address text primary key,
@@ -221,10 +225,6 @@ class BaseDatabase(SQLiteMixin):
         create index if not exists txi_txoid_idx on txi (txoid);
     """
 
-    PRAGMAS = """
-        pragma journal_mode=WAL;
-    """
-
     CREATE_TABLES_QUERY = (
         PRAGMAS +
         CREATE_TX_TABLE +
@@ -480,10 +480,10 @@ class BaseDatabase(SQLiteMixin):
         ) + ', '.join(['(?, ?, ?, ?, ?)'] * len(keys))
         values = []
         for position, pubkey in keys:
-            values.extend([
+            values.extend((
                 pubkey.address, account.public_key.address, chain, position,
                 sqlite3.Binary(pubkey.pubkey_bytes)
-            ])
+            ))
         return self.run_operation(sql, values)
 
     @classmethod