class A:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: G = None
        self.u: G = None
        self.o: B = None
        self.y: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.y: E = None
        self.q: G = None
        self.o: C = None
        self.x: B = None
        self.z: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: E = None
        self.w: D = None
        self.u: C = None
        self.r: B = None
        self.v: G = None
        self.t: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: D = None
        self.r: E = None
        self.txt = txt

d = A("d")
n = B("n")
m = C("m")
i = D("i")
b = E("b")
g = F("g")
j = G("j")
h = E("h")
a = A("a")

d.p = m
d.w = j
d.u = j
d.y = j
d.o = n
n.y = g
m.s = h
m.r = n
i.v = j
i.q = j
i.y = b
i.o = m
i.x = n
i.z = h
b.y = n
b.r = n
b.o = h
b.w = i
b.u = m
b.v = j
b.t = g
g.y = i
j.v = h
j.w = i
j.r = b
h.y = n
h.r = n
h.o = b
h.w = i
h.u = m
h.v = j
h.t = g
a.p = m
a.w = j
a.u = j
a.y = j
a.o = n
assert b.y.y.y.txt == "
class A:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: G = None
        self.u: G = None
        self.o: B = None
        self.y: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.y: E = None
        self.q: G = None
        self.o: C = None
        self.x: B = None
        self.z: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: E = None
        self.w: D = None
        self.u: C = None
        self.r: B = None
        self.v: G = None
        self.t: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: D = None
        self.r: E = None
        self.txt = txt

d = A("d")
n = B("n")
m = C("m")
i = D("i")
b = E("b")
g = F("g")
j = G("j")
h = E("h")
a = A("a")

d.p = m
d.w = j
d.u = j
d.y = j
d.o = n
n.y = g
m.s = h
m.r = n
i.v = j
i.q = j
i.y = b
i.o = m
i.x = n
i.z = h
b.y = n
b.r = n
b.o = h
b.w = i
b.u = m
b.v = j
b.t = g
g.y = i
j.v = h
j.w = i
j.r = b
h.y = n
h.r = n
h.o = b
h.w = i
h.u = m
h.v = j
h.t = g
a.p = m
a.w = j
a.u = j
a.y = j
a.o = n
assert b.y.y.y.txt == "i"