def _bit_size(number):
 if (number < 0):
  raise ValueError(('Only nonnegative numbers possible: %s' % number))
 if (number == 0):
  return 0
 bits = 0
 while number:
  bits += 1
  number >>= 1
 return bits

def _bit_size ( number ) : if ( number < 0 ) : raise ValueError ( ( 'Only nonnegative numbers possible: %s' % number ) ) if ( number == 0 ) : return 0 bits = 0 while number : bits += 1 number >>= 1 return bits
returns the number of bits required to hold a specific long number .