diff --git a/segpy/datatypes.py b/segpy/datatypes.py
index 7d82833..ee02ddd 100644
--- a/segpy/datatypes.py
+++ b/segpy/datatypes.py
@@ -1,39 +1,43 @@
 # A mapping from data sampel format codes to SEG Y types.
-DATA_SAMPLE_FORMAT_TO_SEG_Y_TYPE = {1: 'ibm',
-                      2: 'int32',
-                      3: 'int16',
-                      5: 'float32',
-                      8: 'int8'}
+DATA_SAMPLE_FORMAT_TO_SEG_Y_TYPE = {
+    1: 'ibm',
+    2: 'int32',
+    3: 'int16',
+    5: 'float32',
+    8: 'int8'}
 
 # A mapping from SEG Y data types to format characters used by the struct module
-SEG_Y_TYPE_TO_CTYPE = {'int32':  'i',
-          'uint32': 'I',
-          'int16':  'h',
-          'uint16': 'H',
-          'int8': 'b',
-          'uint8': 'B',
-          'float32':  'f',
-          'ibm': 'ibm'}
+SEG_Y_TYPE_TO_CTYPE = {
+    'int32':  'i',
+    'uint32': 'I',
+    'int16':  'h',
+    'uint16': 'H',
+    'int8': 'b',
+    'uint8': 'B',
+    'float32':  'f',
+    'ibm': 'ibm'}
 
 
-SEG_Y_TYPE_DESCRIPTION = {'ibm': 'IBM float',
-                     'int32': '32 bit signed integer',
-                     'uint32': '32 bit unsigned integer',
-                     'int16': '16 bit signed integer',
-                     'uint16': '16 bit unsigned integer',
-                     'float32': 'IEEE float32',
-                     'int8': '8 bit signed integer (byte)',
-                     'uint8': '8 bit unsigned integer (byte)'}
+SEG_Y_TYPE_DESCRIPTION = {
+    'ibm': 'IBM float',
+    'int32': '32 bit signed integer',
+    'uint32': '32 bit unsigned integer',
+    'int16': '16 bit signed integer',
+    'uint16': '16 bit unsigned integer',
+    'float32': 'IEEE float32',
+    'int8': '8 bit signed integer (byte)',
+    'uint8': '8 bit unsigned integer (byte)'}
 
 
-CTYPE_TO_SIZE = dict(i=4,
-             I=4,
-             h=2,
-             H=2,
-             b=1,
-             B=1,
-             f=4,
-             ibm=4)
+CTYPE_TO_SIZE = dict(
+    i=4,
+    I=4,
+    h=2,
+    H=2,
+    b=1,
+    B=1,
+    f=4,
+    ibm=4)
 
 
 def size_in_bytes(ctype):