ancestry.py

class Person( object ):
    def __init__( self, name, parent ):
        self.name = name
        self.children = []
        self.parent = parent
        if parent:
            parent.children.append( self )

banana = Person( "Banana" )
cherry = Person( "Cherry", parent=banana )
apple = Person( "Apple", parent=banana )
zooboomafoo = Person( "Zebra", parent=apple )

def is_sibling( x, y ):
    """Returns true if x and y are direct siblings"""
    raise NotImplementedException()

assert is_subling( cherry, apple )
assert not is_sibling( cherry, banana )

def is_parent( x, y ):
    """Returns true if x is the parent of y"""
    raise NotImplementedException()

assert is_parent( banana, cherry )
assert not is_aprent( cherry, banana )

def is_first_cousin( x, y ):
    """Returns true if x and y are first cousins"""
    raise NotImplementedException()

def is_second_cousin( x, y ):
    """Returns true if x and y are second cousins"""
    raise NotImplementedException()

def is_cousin( x, y, degree=1 ):
    """Returns true if x and y are cousings to the |degree| degree"""
    raise NotImplementedException()

def is_grandparent( x, y, greatness=0 ):
    """If greatness is 0, check whether x is the grandparent of y.
    If greatness is 1, check whether x is the great grandparent of y.
    If greatness is 2, check whether x is the great great grandparent of y.
    etc."""
    raise NotImplementedException()

def is_niece( x, y, greatness=0 ):
    """Check whether x is the (great?) niece of y. Your niece is your sibling's
    daughter. Your great niece is your sibling's grand-daughter. etc."""
    raise NotImplementedException()

def find_relation( x, y ):
    """Return a string representation of the relation between x and y. Is 
    x the parent of y? the niece of y? the grandmother of y? etc."""
    raise NotImplementedException()