diff --git a/timer.py b/timer.py
index dc090a1..7581531 100644
--- a/timer.py
+++ b/timer.py
@@ -16,6 +16,7 @@ Simple timer utility.
 This module is part of wpylib project.
 """
 
+import sys
 import time
 
 class timer:
@@ -38,6 +39,12 @@ class block_timer(object):
 
       with block_timer() as t:
         <code>
+
+  Fancy options are available to record the timing result, specified when
+  initializing the new object:
+
+  * report=block_timer.writeout_file :: writes out the timing result to a file
+  * report=block_timer.writeout_dict :: saves the timing result to a dict-like element
   """
   @staticmethod
   def writeout_file(out):
@@ -49,21 +56,23 @@ class block_timer(object):
     return wrt_dict
     #return lambda tm: rec.__setitem__(key, tm)
 
-  @staticmethod
-  def bt_file(fobj):
+  @classmethod
+  def bt_file(cls, fobj):
+    """An object factory to report the timing to a text file.
+    """
     if isinstance(fobj, basestring):
       from wpylib.iofmt.text_output import text_output
       out = text_output(fobj)
     else:
       out = fobj
-    return block_timer(report=block_timer.writeout_file(out))
+    return cls(report=block_timer.writeout_file(out))
 
-  @staticmethod
-  def bt_dict(rec, key):
-    return block_timer(report=block_timer.writeout_dict(rec, key))
+  @classmethod
+  def bt_dict(cls, rec, key):
+    return cls(report=block_timer.writeout_dict(rec, key))
 
   def __init__(self, report=None):
-    if report == None: report = block_timer.writeout_file(sys.stdout)
+    if report is None: report = block_timer.writeout_file(sys.stdout)
     self.report = report
 
   def __enter__(self):