imports, whitespace

electrum/blockchain.py

@@ -46,9 +46,11 @@ MAX_TARGET = 0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff
 class MissingHeader(Exception):
     pass
 
+
 class InvalidHeader(Exception):
     pass
 
+
 def serialize_header(header_dict: dict) -> bytes:
     s = (
         int.to_bytes(header_dict['version'], length=4, byteorder="little", signed=False)
@@ -59,6 +61,7 @@ def serialize_header(header_dict: dict) -> bytes:
         + int.to_bytes(int(header_dict['nonce']), length=4, byteorder="little", signed=False))
     return s
 
+
 def deserialize_header(s: bytes, height: int) -> dict:
     if not s:
         raise InvalidHeader('Invalid header: {}'.format(s))
@@ -74,6 +77,7 @@ def deserialize_header(s: bytes, height: int) -> dict:
     h['block_height'] = height
     return h
 
+
 def hash_header(header: dict) -> str:
     if header is None:
         return '0' * 64
@@ -161,6 +165,7 @@ def read_blockchains(config: 'SimpleConfig'):
 def get_best_chain() -> 'Blockchain':
     return blockchains[constants.net.GENESIS]
 
+
 # block hash -> chain work; up to and including that block
 _CHAINWORK_CACHE = {
     "0000000000000000000000000000000000000000000000000000000000000000": 0,  # virtual block at height -1