Minor Python cleanups to make flake8 pass with the new rules enabled

9 files changed, 30 insertions, 26 deletions

diff --git a/contrib/devtools/copyright_header.py b/contrib/devtools/copyright_header.py
index c817e794b9..e7cccaab03 100755
--- a/contrib/devtools/copyright_header.py
+++ b/contrib/devtools/copyright_header.py
@@ -286,7 +286,7 @@ Arguments:
 def report_cmd(argv):
     if len(argv) == 2:
         sys.exit(REPORT_USAGE)
-        
+
     base_directory = argv[2]
     if not os.path.exists(base_directory):
         sys.exit("*** bad <base_directory>: %s" % base_directory)
@@ -444,7 +444,7 @@ def print_file_action_message(filename, action):
 def update_cmd(argv):
     if len(argv) != 3:
         sys.exit(UPDATE_USAGE)
-    
+
     base_directory = argv[2]
     if not os.path.exists(base_directory):
         sys.exit("*** bad base_directory: %s" % base_directory)
@@ -570,13 +570,13 @@ def insert_cmd(argv):
     _, extension = os.path.splitext(filename)
     if extension not in ['.h', '.cpp', '.cc', '.c', '.py']:
         sys.exit("*** cannot insert for file extension %s" % extension)
-   
+
     if extension == '.py': 
         style = 'python'
     else:
         style = 'cpp'
     exec_insert_header(filename, style)
-         
+
 ################################################################################
 # UI
 ################################################################################
diff --git a/contrib/devtools/github-merge.py b/contrib/devtools/github-merge.py
index 9c666673cf..187ef75fb7 100755
--- a/contrib/devtools/github-merge.py
+++ b/contrib/devtools/github-merge.py
@@ -21,7 +21,8 @@ import argparse
 import hashlib
 import subprocess
 import sys
-import json,codecs
+import json
+import codecs
 try:
     from urllib.request import Request,urlopen
 except:
diff --git a/contrib/devtools/optimize-pngs.py b/contrib/devtools/optimize-pngs.py
index 565b199125..a75731ef76 100755
--- a/contrib/devtools/optimize-pngs.py
+++ b/contrib/devtools/optimize-pngs.py
@@ -41,19 +41,19 @@ for folder in folders:
             file_path = os.path.join(absFolder, file)
             fileMetaMap = {'file' : file, 'osize': os.path.getsize(file_path), 'sha256Old' : file_hash(file_path)}
             fileMetaMap['contentHashPre'] = content_hash(file_path)
-        
+
             try:
                 subprocess.call([pngcrush, "-brute", "-ow", "-rem", "gAMA", "-rem", "cHRM", "-rem", "iCCP", "-rem", "sRGB", "-rem", "alla", "-rem", "text", file_path],
                                 stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
             except:
                 print("pngcrush is not installed, aborting...")
                 sys.exit(0)
-        
+
             #verify
             if "Not a PNG file" in subprocess.check_output([pngcrush, "-n", "-v", file_path], stderr=subprocess.STDOUT, universal_newlines=True):
                 print("PNG file "+file+" is corrupted after crushing, check out pngcursh version")
                 sys.exit(1)
-            
+
             fileMetaMap['sha256New'] = file_hash(file_path)
             fileMetaMap['contentHashPost'] = content_hash(file_path)
 
@@ -72,5 +72,5 @@ for fileDict in outputArray:
     totalSaveBytes += fileDict['osize'] - fileDict['psize']
     noHashChange = noHashChange and (oldHash == newHash)
     print(fileDict['file']+"\n  size diff from: "+str(fileDict['osize'])+" to: "+str(fileDict['psize'])+"\n  old sha256: "+oldHash+"\n  new sha256: "+newHash+"\n")
-    
+
 print("completed. Checksum stable: "+str(noHashChange)+". Total reduction: "+str(totalSaveBytes)+" bytes")
diff --git a/contrib/linearize/linearize-data.py b/contrib/linearize/linearize-data.py
index 4969e96827..c609e9b336 100755
--- a/contrib/linearize/linearize-data.py
+++ b/contrib/linearize/linearize-data.py
@@ -21,7 +21,6 @@ from binascii import hexlify, unhexlify
 
 settings = {}
 
-##### Switch endian-ness #####
 def hex_switchEndian(s):
 	""" Switches the endianness of a hex string (in pairs of hex chars) """
 	pairList = [s[i:i+2].encode() for i in range(0, len(s), 2)]
diff --git a/contrib/linearize/linearize-hashes.py b/contrib/linearize/linearize-hashes.py
index 6b69c5b3a3..e1304e26d0 100755
--- a/contrib/linearize/linearize-hashes.py
+++ b/contrib/linearize/linearize-hashes.py
@@ -21,7 +21,6 @@ import os.path
 
 settings = {}
 
-##### Switch endian-ness #####
 def hex_switchEndian(s):
 	""" Switches the endianness of a hex string (in pairs of hex chars) """
 	pairList = [s[i:i+2].encode() for i in range(0, len(s), 2)]
diff --git a/contrib/seeds/generate-seeds.py b/contrib/seeds/generate-seeds.py
index 2790ef4acd..72eb7255f3 100755
--- a/contrib/seeds/generate-seeds.py
+++ b/contrib/seeds/generate-seeds.py
@@ -34,7 +34,8 @@ These should be pasted into `src/chainparamsseeds.h`.
 
 from base64 import b32decode
 from binascii import a2b_hex
-import sys, os
+import sys
+import os
 import re
 
 # ipv4 in ipv6 prefix
@@ -46,7 +47,7 @@ def name_to_ipv6(addr):
     if len(addr)>6 and addr.endswith('.onion'):
         vchAddr = b32decode(addr[0:-6], True)
         if len(vchAddr) != 16-len(pchOnionCat):
-            raise ValueError('Invalid onion %s' % s)
+            raise ValueError('Invalid onion %s' % vchAddr)
         return pchOnionCat + vchAddr
     elif '.' in addr: # IPv4
         return pchIPv4 + bytearray((int(x) for x in addr.split('.')))
@@ -132,7 +133,7 @@ def main():
     with open(os.path.join(indir,'nodes_test.txt'),'r') as f:
         process_nodes(g, f, 'pnSeed6_test', 18333)
     g.write('#endif // BITCOIN_CHAINPARAMSSEEDS_H\n')
-            
+
 if __name__ == '__main__':
     main()
 
diff --git a/contrib/seeds/makeseeds.py b/contrib/seeds/makeseeds.py
index 6e253c994d..59044e701a 100755
--- a/contrib/seeds/makeseeds.py
+++ b/contrib/seeds/makeseeds.py
@@ -6,6 +6,11 @@
 # Generate seeds.txt from Pieter's DNS seeder
 #
 
+import re
+import sys
+import dns.resolver
+import collections
+
 NSEEDS=512
 
 MAX_SEEDS_PER_ASN=2
@@ -22,11 +27,6 @@ SUSPICIOUS_HOSTS = {
     "54.94.195.96", "54.94.200.247"
 }
 
-import re
-import sys
-import dns.resolver
-import collections
-
 PATTERN_IPV4 = re.compile(r"^((\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})):(\d+)$")
 PATTERN_IPV6 = re.compile(r"^\[([0-9a-z:]+)\]:(\d+)$")
 PATTERN_ONION = re.compile(r"^([abcdefghijklmnopqrstuvwxyz234567]{16}\.onion):(\d+)$")
diff --git a/contrib/testgen/base58.py b/contrib/testgen/base58.py
index 0dbb79a707..071bc722b0 100644
--- a/contrib/testgen/base58.py
+++ b/contrib/testgen/base58.py
@@ -43,8 +43,10 @@ def b58encode(v):
     # leading 0-bytes in the input become leading-1s
     nPad = 0
     for c in v:
-        if c == 0: nPad += 1
-        else: break
+        if c == 0:
+            nPad += 1
+        else:
+            break
 
     return (__b58chars[0]*nPad) + result
 
@@ -98,7 +100,8 @@ def b58decode_chk(v):
 def get_bcaddress_version(strAddress):
     """ Returns None if strAddress is invalid.  Otherwise returns integer version of address. """
     addr = b58decode_chk(strAddress)
-    if addr is None or len(addr)!=21: return None
+    if addr is None or len(addr)!=21:
+        return None
     version = addr[0]
     return ord(version)
 
diff --git a/contrib/testgen/gen_base58_test_vectors.py b/contrib/testgen/gen_base58_test_vectors.py
index 4351605786..de15657d27 100755
--- a/contrib/testgen/gen_base58_test_vectors.py
+++ b/contrib/testgen/gen_base58_test_vectors.py
@@ -74,12 +74,12 @@ def gen_invalid_vector(template, corrupt_prefix, randomize_payload_size, corrupt
         prefix = os.urandom(1)
     else:
         prefix = bytearray(template[0])
-    
+
     if randomize_payload_size:
         payload = os.urandom(max(int(random.expovariate(0.5)), 50))
     else:
         payload = os.urandom(template[1])
-    
+
     if corrupt_suffix:
         suffix = os.urandom(len(template[2]))
     else:
@@ -114,7 +114,8 @@ def gen_invalid_vectors():
                 yield val,
 
 if __name__ == '__main__':
-    import sys, json
+    import sys
+    import json
     iters = {'valid':gen_valid_vectors, 'invalid':gen_invalid_vectors}
     try:
         uiter = iters[sys.argv[1]]
@@ -124,7 +125,7 @@ if __name__ == '__main__':
         count = int(sys.argv[2])
     except IndexError:
         count = 0
-   
+
     data = list(islice(uiter(), count))
     json.dump(data, sys.stdout, sort_keys=True, indent=4)
     sys.stdout.write('\n')