class A:
    def __init__(self, txt: str):
        self.p: E = None
        self.u: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: A = None
        self.u: D = None
        self.w: G = None
        self.y: H = None
        self.r: D = None
        self.s: G = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: E = None
        self.z: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: E = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.t: G = None
        self.o: D = None
        self.p: C = None
        self.r: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: H = None
        self.q: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: G = None
        self.o: E = None
        self.r: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: A = None
        self.u: D = None
        self.w: G = None
        self.y: H = None
        self.r: D = None
        self.s: G = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: E = None
        self.z: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: E = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.t: G = None
        self.o: D = None
        self.p: C = None
        self.r: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: H = None
        self.q: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: G = None
        self.o: E = None
        self.r: C = None
        self.txt = txt

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

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