diff --git a/bob/bio/base/algorithm/Algorithm.py b/bob/bio/base/algorithm/Algorithm.py
index 990c2093937a43dab78388d38e0a3b0996b05e82..38834b8fa45d6484f1c9927d250f2cd5e654bb78 100644
--- a/bob/bio/base/algorithm/Algorithm.py
+++ b/bob/bio/base/algorithm/Algorithm.py
@@ -7,7 +7,7 @@ import numpy
 import os
 from .. import utils
 
-class Algorithm:
+class Algorithm (object):
   """This is the base class for all biometric recognition algorithms.
   It defines the minimum requirements for all derived algorithm classes.
 
diff --git a/bob/bio/base/extractor/Extractor.py b/bob/bio/base/extractor/Extractor.py
index 251d6283e2a1f2e68b9e364726379e7f79fc32bc..fc09fb62135f97465942d16e75dd576631aa523e 100644
--- a/bob/bio/base/extractor/Extractor.py
+++ b/bob/bio/base/extractor/Extractor.py
@@ -7,7 +7,7 @@ import os
 
 from .. import utils
 
-class Extractor:
+class Extractor (object):
   """This is the base class for all feature extractors.
   It defines the minimum requirements that a derived feature extractor class need to implement.
 
diff --git a/bob/bio/base/grid.py b/bob/bio/base/grid.py
index def7125b0920f830f3de2dc743499d41da71efc9..6390661377eb5fbc73383d8c0df8c8c965bae3ff 100644
--- a/bob/bio/base/grid.py
+++ b/bob/bio/base/grid.py
@@ -21,7 +21,7 @@ PREDEFINED_QUEUES = {
 
 from . import utils
 
-class Grid:
+class Grid (object):
   """This class is defining the options that are required to submit parallel jobs to the SGE grid, or jobs to the local queue.
 
   If the given ``grid_type`` is ``'sge'`` (the default), this configuration is set up to submit algorithms to the SGE grid.
diff --git a/bob/bio/base/preprocessor/Preprocessor.py b/bob/bio/base/preprocessor/Preprocessor.py
index ab3bb1c6fff0fc97aa8035f324e6b46eeed33993..b8382b08b583af172afc386e8caf343f2e92ef43 100644
--- a/bob/bio/base/preprocessor/Preprocessor.py
+++ b/bob/bio/base/preprocessor/Preprocessor.py
@@ -6,7 +6,7 @@
 from .. import utils
 
 
-class Preprocessor:
+class Preprocessor (object):
     """This is the base class for all preprocessors.
     It defines the minimum requirements for all derived proprocessor classes.
 
diff --git a/bob/bio/base/tools/grid.py b/bob/bio/base/tools/grid.py
index cb04d88a12530adae3e7aad7fb9d458583097245..909ac2091143548f8bcfe1e79be19e930dea7b9e 100644
--- a/bob/bio/base/tools/grid.py
+++ b/bob/bio/base/tools/grid.py
@@ -32,7 +32,7 @@ def indices(list_to_split, number_of_parallel_jobs, task_id=None):
     return (start, end)
 
 
-class GridSubmission:
+class GridSubmission (object):
   def __init__(self, args, command_line_parameters, executable = 'verify.py', first_fake_job_id = 0):
     # find, where the executable is installed
     import bob.extension
@@ -49,7 +49,7 @@ class GridSubmission:
 
     if args.grid is not None:
       assert isinstance(args.grid, grid.Grid)
-      
+
       self.env = args.env #Fetching the enviroment variable
 
       # find, where jman is installed