Hiererachy of quadrilaterals

quads.py

class trapezium():
    
    """
    Trapezium class that takes three parameters two of it's 
    parallel sides(a & b) and height(h)
    
    >>> t1 = trapezium(2,2,4)
    >>> t1.area
    8
    >>>t2  = trapezium.(2,2,4,2,2)
    8

    """

    def __init__(self, a, b, h, *args):
        self._a = a
        self._b = b
        self._h = h
        if len(args)==2:
            self._c = args[0]
            self._d = args[1]

    @property
    def area(self):
        try:
            return .5 * (self._a * self._b)*(self._h)
        except:
            print ("Invalid operation")

    @property
    def perimeter(self):
        try:
            return self._a + self._b + self._c + self._d
        except:
            print ("Invalid operation")

class parallelogram(trapezium):

    """Parallelogram class takes a,b and h
    >>> t1 = parallelogram(2,2,4)
    >>> t1.area
    8
    >>>t1.perimeter
    8


    """

    def ___init__(self, a, b, h):
        self._a = a
        self._h = h
        self._b = b

    @property
    def area(self):
        try:
            return self._a * self._h 
        except:
            print ("Invalid operation")

    @property
    def perimeter(self):
        try:
            return 2*(self._a + self._b)
        except:
            print ("Invalid operation")


class rectangle(parallelogram):

    """
    Rectangle takes a,b
    >>> t1 = rectangle(2,4)
    >>> t1.area
    8
    >>>t1.perimeter
    12

    """
    def __init__(self, a, b):
        self._a = a
        self._b = b
    
    @property
    def area(self):
        try:
            return self._a * self._b 
        except:
            print ("Invalid operation")

    @property
    def perimeter(self):
        try:
            return 2*(self._a + self._b)
        except:
            print ("Invalid operation")


class rhombus(trapezium):
    """
    Rectangle takes a,b
    >>> t1 = rhombus(2)
    >>> t1.perimeter
    8
    >>>t2 = rhombus(5, 6, 8)
    24
    """

    def __init__(self, a, *args):
        self._a = a
        if len(args)==2:
            self._d1 = args[0]
            self._d2 = args[1]
    @property
    def area(self):
        try:
            return .5 * self._d1 * self._d2 
        except:
            print ("Invalid operation")

    @property
    def perimeter(self):
        try:
            return 4*self._a  
        except:
            print ("Invalid operation")




class square(rectangle):
    """
    Square takes a
    >>> t1 = square(2)
    >>> t1.perimeter
    8
    >>>t1.area
    9
    """
    def __init__(self, a):
        self._a = a
        self._d = ((2)**.5)*a

    @property
    def area(self):
        try:
            return self._a **2
        except:
            print ("Invalid operation")

    @property
    def perimeter(self):
        try:
            return 4*(self._a)
        except:
            print ("Invalid operation")


if __name__=="main":
    import doctest
    doctest.testmod()