Update contribs script

doc/release/contribs.py

@@ -1,5 +1,5 @@
 # https://github.com/scikit-image/scikit-image/blob/master/doc/release/contribs.py
-import subprocess
+from subprocess import check_output
 import sys
 import string
 import shlex
@@ -10,45 +10,50 @@
 
 tag = sys.argv[1]
 
+
 def call(cmd):
-    return subprocess.check_output(shlex.split(cmd), universal_newlines=True).split('\n')
+    return check_output(shlex.split(cmd), universal_newlines=True).split("\n")
+
 
-tag_date = call("git log -n1 --format='%%ci' %s" % tag)[0]
-print("Release %s was on %s\n" % (tag, tag_date))
+tag_date = call(f"git log -n1 --format='%ci' {tag}")[0]
+print(f"Release {tag} was on {tag_date}\n")
 
-merges = call("git log --since='%s' --merges --format='>>>%%B' --reverse" % tag_date)
+merges = call(f"git log --since='{tag_date}' --merges --format='>>>%B' --reverse")
 merges = [m for m in merges if m.strip()]
-merges = '\n'.join(merges).split('>>>')
-merges = [m.split('\n')[:2] for m in merges]
+merges = "\n".join(merges).split(">>>")
+merges = [m.split("\n")[:2] for m in merges]
 merges = [m for m in merges if len(m) == 2 and m[1].strip()]
 
-num_commits = call("git rev-list %s..HEAD --count" % tag)[0]
-print("A total of %s changes have been committed.\n" % num_commits)
+num_commits = call(f"git rev-list {tag}..HEAD --count")[0]
+print(f"A total of {num_commits} changes have been committed.\n")
 
-commits = call("git log --since='%s' --pretty=%%s --reverse" % tag_date)
+# Use filter to remove empty strings
+commits = filter(None, call(f"git log --since='{tag_date}' --pretty=%s --reverse"))
 for c in commits:
-    print('- ' + c)
+    print("- " + c)
 
-print("It contained the following %d merges:\n" % len(merges))
+print(f"\nIt contained the following {len(merges)} merges:\n")
 for (merge, message) in merges:
-    if merge.startswith('Merge pull request #'):
-        PR = ' (%s)' % merge.split()[3]
+    if merge.startswith("Merge pull request #"):
+        PR = f" ({merge.split()[3]})"
     else:
-        PR = ''
+        PR = ""
 
-    print('- ' + message + PR)
+    print("- " + message + PR)
 
 print("\nMade by the following committers [alphabetical by last name]:\n")
 
-authors = call("git log --since='%s' --format=%%aN" % tag_date)
+authors = call(f"git log --since='{tag_date}' --format=%aN")
 authors = [a.strip() for a in authors if a.strip()]
 
+
 def key(author):
     author = [v for v in author.split() if v[0] in string.ascii_letters]
     if len(author) > 0:
         return author[-1]
 
+
 authors = sorted(set(authors), key=key)
 
 for a in authors:
-    print('- ' + a)
+    print("- " + a)