add python function indent

add python function indent

source/c06/p05_turning_dictionary_into_xml.rst

@@ -18,15 +18,15 @@
     from xml.etree.ElementTree import Element
 
     def dict_to_xml(tag, d):
-    '''
-    Turn a simple dict of key/value pairs into XML
-    '''
-    elem = Element(tag)
-    for key, val in d.items():
-        child = Element(key)
-        child.text = str(val)
-        elem.append(child)
-    return elem
+        '''
+        Turn a simple dict of key/value pairs into XML
+        '''
+        elem = Element(tag)
+        for key, val in d.items():
+            child = Element(key)
+            child.text = str(val)
+            elem.append(child)
+        return elem
 
 下面是一个使用例子：