Money data type

[Phil Schmidt]

Try this:
-------------------------
import types

class USD:
    """
    This class represents money in US Dollars, does math on it,
    prints it, etc. All dollar amounts are stored in cents, and no
    fractional cents are allowed. Rounding is supported for fractional
    cent values that are passed in.
    """
    def __init__(self, value=0):
        """U.S. Dollars, stored in cents."""
        if isinstance(value, USD):
            self.value = value.value
        else:
            self.value = int(round(value * 100))

    def __repr__(self):
    	"""This is returns a string that may be exec'ed to get a duplicate."""
    	s = '%03i' % self.value
    	s = 'USD(%s.%s)' % (s[:-2], s[-2:])
    	return s
    
    def __str__(self):
    	"""return a nice formatted printable string"""
    	return '$%9.2f' % (float(self.value) / 100)

    def STR(self):
        """return a 'raw' formatted printable string"""
    	return '%0.2f' % (float(self.value) / 100)

    def __add__(self, value):
    	"""perform self + value"""
        # handle the case where value is a string
        if type(value) is types.StringType:
            return self.__str__() + value
        # otherwise it's assumed to be a numeric type
    	m = USD(value)
    	m.value += self.value
    	return m
    
    def __radd__(self, value):
    	"""perform value + self"""
        # handle the case where value is a string
        if type(value) is types.StringType:
            return value + self.__str__()
        # otherwise it's assumed to be a numeric type
    	m = USD(value)
    	m.value += self.value
    	return m
    
    def __sub__(self, value):
    	"""returns a USD instance containing the difference between self and value"""
    	m = USD(value)
    	m.value = self.value - m.value
    	return m
    
    def __rsub__(self, value):
    	"""returns a USD instance containing the difference between value and self"""
    	m = USD(value)
    	m.value -= self.value
    	return m

    def __iadd__(self, value):
    	"""perform self += value"""
    	m = USD(value)
    	self.value += m.value
    	return self

    def __isub__(self, value):
    	"""perform self -= value"""
    	m = USD(value)
    	self.value -= m.value
    	return self
    
    def __neg__(self):
    	"""return negated self"""
    	m = USD()
    	m.value = -self.value
    	return m
    
    def __pos__(self):
    	"""return self"""
    	m = USD()
    	m.value = self.value
    	return m
    
    def __lt__(self, value):
    	"""perform self < value"""
    	m = USD(value)
    	return self.value < m.value
    def __gt__(self, value):
    	"""perform self > value"""
    	m = USD(value)
    	return self.value > m.value
    
    def __eq__(self, value):
    	"""perform self == value"""
    	m = USD(value)
    	return self.value == m.value
    
    def __ne__(self, value):
    	"""perform self != value"""
    	m = USD(value)
    	return self.value != m.value
    
    def __le__(self, value):
    	"""perform self < value"""
    	m = USD(value)
    	return self.value <= m.value
    
    def __ge__(self, value):
    	"""perform self < value"""
    	m = USD(value)
    	return self.value >= m.value