old_contents: 
  def human(size):
  	radix = 1024.
  	units = ["B", "KB", "MB", "GB", "TB"]
  	n = len(units)
  	for u in range(n):
  		if size < radix : break
  		size /= radix
  
  	return "%f %s" % (size, units[u])
  
new_contents: 
  def human ( size ) :
  
  	"""
  
  		>>> from lib.bytes import *
  		>>> human( 23 )
  		'23.000000 B'
  		>>> human( 1024 )
  		'1.000000 KB'
  		>>> human( 1025 )
  		'1.000977 KB'
  		>>> human( 1024 ** 4 )
  		'1.000000 TB'
  		>>> human( 1024 ** 5 )
  		'1024.000000 TB'
  
  	"""
  
  	radix = 1024.
  	units = ["B", "KB", "MB", "GB", "TB"]
  	last = units[-1]
  
  	for u in units :
  		if u == last or size < radix : break
  		size /= radix
  
  	return "%f %s" % ( size , u )
  
subject: increase coverage