Put code in a main() function; loosen up the spacing to match current code style

Demo/zlib/zlibdemo.py

@@ -1,10 +1,19 @@
 #!/usr/bin/env python
 
+# Takes an optional filename, defaulting to this file itself.
+# Reads the file and compresses the content using level 1 and level 9
+# compression, printing a summary of the results.
+
 import zlib, sys
-if len(sys.argv)>1: filename=sys.argv[1]
+
-else: filename='zlibdemo.py'
+def main():
+    if len(sys.argv) > 1:
+        filename = sys.argv[1]
+    else:
+        filename = sys.argv[0]
     print 'Reading', filename
-f=open(filename, 'r')           # Get the data to compress
+
+    f = open(filename, 'rb')           # Get the data to compress
     s = f.read()
     f.close()
 
@@ -24,7 +33,8 @@ decompressor=zlib.decompressobj()
     comptext = decomp = ''
     for i in range(0, len(s), chunk):
         comptext = comptext+compressor.compress(s[i:i+chunk])
-comptext=comptext+compressor.flush()    # Don't forget to call flush()!!
+    # Don't forget to call flush()!!
+    comptext = comptext + compressor.flush()
 
     for i in range(0, len(comptext), chunk):
         decomp = decomp + decompressor.decompress(comptext[i:i+chunk])
@@ -33,3 +43,6 @@ decomp=decomp+decompressor.flush()
     print 'Progressive compression (level 9):'
     print '    Original:', len(s), 'Compressed:', len(comptext),
     print 'Uncompressed:', len(decomp)
+
+if __name__ == '__main__':
+    main()