diff --git a/doc/data/sdss_colors/fetch_data.py b/doc/data/sdss_colors/fetch_data.py
index 8dcfbd9..330ecd9 100644
--- a/doc/data/sdss_colors/fetch_data.py
+++ b/doc/data/sdss_colors/fetch_data.py
@@ -1,5 +1,12 @@
+from __future__ import print_function
+
 import os
-import urllib2
+# Supporting Python 2 and 3
+try:
+    import urllib.request as urllib2
+except ImportError:
+    import urllib2
+
 import numpy as np
 
 DTYPE_TRAIN = [('u-g', np.float32),
@@ -28,7 +35,7 @@
 destination = TRAIN_FILE.rstrip('.dat') + '.npy'
 if not os.path.exists(destination):
     url = SDSS_COLORS_URL + TRAIN_FILE
-    print "downloading data from", url
+    print("downloading data from", url)
     fhandle = opener.open(url)
     np.save(destination, np.loadtxt(opener.open(url), dtype=DTYPE_TRAIN))
 
@@ -36,7 +43,7 @@
 destination = TEST_FILE.rstrip('.dat') + '.npy'
 if not os.path.exists(destination):
     url = SDSS_COLORS_URL + TEST_FILE
-    print "downloading data from", url
+    print("downloading data from", url)
     fhandle = opener.open(url)
     np.save(destination, np.loadtxt(opener.open(url), dtype=DTYPE_TEST))
 
diff --git a/doc/data/sdss_colors/scatter_colors.py b/doc/data/sdss_colors/scatter_colors.py
index 555a94a..78c142e 100644
--- a/doc/data/sdss_colors/scatter_colors.py
+++ b/doc/data/sdss_colors/scatter_colors.py
@@ -1,3 +1,4 @@
+from __future__ import print_function
 import numpy as np
 import pylab as pl
 
@@ -9,8 +10,8 @@
 
 redshift = data['redshift']
 
-print "%i qsos" % np.sum(redshift > 0)
-print "%i stars" % np.sum(redshift == 0)
+print("%i qsos" % np.sum(redshift > 0))
+print("%i stars" % np.sum(redshift == 0))
 
 kwargs = dict(s=1, c=(redshift > 0), lw=0)
 
diff --git a/doc/data/sdss_photoz/fetch_data.py b/doc/data/sdss_photoz/fetch_data.py
index fe19ea4..1d060d0 100644
--- a/doc/data/sdss_photoz/fetch_data.py
+++ b/doc/data/sdss_photoz/fetch_data.py
@@ -4,9 +4,15 @@
 queries the SDSS database for the information, and thus can take a few
 minutes to run.
 """
-
+from __future__ import print_function
 import os
-import urllib, urllib2
+import urllib
+# Supporting Python 2 and 3
+try:
+    import urllib.request as urllib2
+except ImportError:
+    import urllib2
+
 import numpy as np
 
 # Here's how the data can be downloaded directly from the SDSS server.
@@ -42,17 +48,17 @@ def sql_query(sql_str, url=URL, format='csv'):
 
 
     if not os.path.exists(archive_file):
-        print "querying for %i objects" % N
-        print query_text
+        print("querying for %i objects" % N)
+        print(query_text)
         output = sql_query(query_text)
-        print "finished.  Processing & saving data"
+        print("finished.  Processing & saving data")
         try:
             data = np.loadtxt(output, delimiter=',', skiprows=1, dtype=DTYPE)
         except:
             raise ValueError(output.read())
         np.save(archive_file, data)
     else:
-        print "data already on disk"
+        print("data already on disk")
 
 
 DATA_URL = ('http://www.astro.washington.edu/users/'
@@ -67,6 +73,6 @@ def sql_query(sql_str, url=URL, format='csv'):
 
 # download training data
 if not os.path.exists(LOCAL_FILE):
-    print "downloading data from", DATA_URL
+    print("downloading data from", DATA_URL)
     fhandle = opener.open(DATA_URL)
     open(LOCAL_FILE, 'wb').write(fhandle.read())
diff --git a/doc/data/sdss_spectra/fetch_data.py b/doc/data/sdss_spectra/fetch_data.py
index f576019..9c97ca6 100644
--- a/doc/data/sdss_spectra/fetch_data.py
+++ b/doc/data/sdss_spectra/fetch_data.py
@@ -1,5 +1,12 @@
+from __future__ import print_function
 import os
-import urllib2
+
+# Supporting Python 2 and 3
+try:
+    import urllib.request as urllib2
+except ImportError:
+    import urllib2
+
 import numpy as np
 
 DATA_URL = ('http://www.astro.washington.edu/users/'
@@ -14,6 +21,6 @@
 
 # download training data
 if not os.path.exists(LOCAL_FILE):
-    print "downloading data from", DATA_URL
+    print("downloading data from", DATA_URL)
     fhandle = opener.open(DATA_URL)
     open(LOCAL_FILE, 'wb').write(fhandle.read())