fix code style

Author: zjffdu

python/pyspark/sql/column.py

@@ -269,19 +269,19 @@ def substr(self, startPos, length):
         if isinstance(startPos, (int, long)):
             javaMaxInt = 2147483647
             if startPos > javaMaxInt:
-               raise ValueError("startPos is larger than the java max int value "
-                                "which is not supported by pyspark, startPos=" + str(startPos))
+                raise ValueError("startPos is larger than the java max int value "
+                                 "which is not supported by pyspark, startPos=" + str(startPos))
 
             if length == sys.maxint:
                 # length == sys.maxint when using syntax str[1:]
                 # cut it down to java max int because java api of substr only support int type
                 # of length
                 warnings.warn("PySpark's substr only support int type of length, "
-                                "please make sure the length you specify is less than 2147483647")
+                              "please make sure the length you specify is less than 2147483647")
                 length = javaMaxInt
             elif length > javaMaxInt:
                 raise ValueError("length is larger than the java max int value "
-                                "which is not supported by pyspark, length=" + str(length))
+                                 "which is not supported by pyspark, length=" + str(length))
 
             jc = self._jc.substr(startPos, length)
         elif isinstance(startPos, Column):