remove dead code

lib/blockchain.py

@@ -159,15 +159,6 @@ class Blockchain(util.PrintError):
         if int('0x' + _hash, 16) > target:
             raise BaseException("insufficient proof of work: %s vs target %s" % (int('0x' + _hash, 16), target))
 
-    def verify_chain(self, chain):
-        first_header = chain[0]
-        prev_header = self.read_header(first_header.get('block_height') - 1)
-        for header in chain:
-            height = header.get('block_height')
-            bits, target = self.get_target(height / 2016, chain)
-            self.verify_header(header, prev_header, bits, target)
-            prev_header = header
-
     def verify_chunk(self, index, data):
         num = len(data) / 80
         prev_header = None
@@ -275,18 +266,13 @@ class Blockchain(util.PrintError):
         h = self.local_height
         return sum([self.BIP9(h-i, 2) for i in range(N)])*10000/N/100.
 
-    def get_target(self, index, chain=None):
+    def get_target(self, index):
         if bitcoin.TESTNET:
             return 0, 0
         if index == 0:
             return 0x1d00ffff, MAX_TARGET
         first = self.read_header((index-1) * 2016)
         last = self.read_header(index*2016 - 1)
-        if last is None:
-            for h in chain:
-                if h.get('block_height') == index*2016 - 1:
-                    last = h
-        assert last is not None
         # bits to target
         bits = last.get('bits')
         bitsN = (bits >> 24) & 0xff