code: def eth_getStorageAt(self, address, position=0, block=BLOCK_TAG_LATEST):
          
          block = validate_block(block)
          return hex_to_dec((yield from self.rpc_call('eth_getStorageAt',
                                                      [address,
                                                       hex(position),
                                                       block])))
docs: https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_getstorageat
  
          :param address: Storage address
          :type address: str
  
          :param position: Position in storage (optional)
          :type position: int
  
          :param block: Block tag or number (optional)
          :type block: int or BLOCK_TAGS
  
          :rtype: int