pep8-ify sample code

docs/graphics-protocol.rst

@@ -97,32 +97,36 @@ features of the graphics protocol:
 
 .. code-block:: python
 
-   import sys
-   from base64 import standard_b64encode
+    import sys
+    from base64 import standard_b64encode
 
-   def serialize_gr_command(**cmd):
-      payload = cmd.pop('payload', None)
-      cmd = ','.join('{}={}'.format(k, v) for k, v in cmd.items())
-      ans = []
-      w = ans.append
-      w(b'\033_G'), w(cmd.encode('ascii'))
-      if payload:
-         w(b';')
-         w(payload)
-      w(b'\033\\')
-      return b''.join(ans)
 
-   def write_chunked(**cmd):
-      data = standard_b64encode(cmd.pop('data'))
-      while data:
-         chunk, data = data[:4096], data[4096:]
-         m = 1 if data else 0
-         sys.stdout.buffer.write(serialize_gr_command(payload=chunk, m=m, **cmd))
-         sys.stdout.flush()
-         cmd.clear()
+    def serialize_gr_command(**cmd):
+        payload = cmd.pop('payload', None)
+        cmd = ','.join('{}={}'.format(k, v) for k, v in cmd.items())
+        ans = []
+        w = ans.append
+        w(b'\033_G'), w(cmd.encode('ascii'))
+        if payload:
+            w(b';')
+            w(payload)
+        w(b'\033\\')
+        return b''.join(ans)
 
-   with open(sys.argv[-1], 'rb') as f:
-      write_chunked(a='T', f=100, data=f.read())
+
+    def write_chunked(**cmd):
+        data = standard_b64encode(cmd.pop('data'))
+        while data:
+            chunk, data = data[:4096], data[4096:]
+            m = 1 if data else 0
+            sys.stdout.buffer.write(serialize_gr_command(payload=chunk, m=m,
+                                                        **cmd))
+            sys.stdout.flush()
+            cmd.clear()
+
+
+    with open(sys.argv[-1], 'rb') as f:
+        write_chunked(a='T', f=100, data=f.read())
 
 
 Save this script as :file:`png.py`, then you can use it to display any PNG