class A:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: G = None
        self.y: D = None
        self.v: H = None
        self.t: G = None
        self.o: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.t: E = None
        self.x: D = None
        self.p: I = None
        self.w: G = None
        self.q: G = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.o: G = None
        self.z: I = None
        self.p: I = None
        self.u: C = None
        self.x: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.r: F = None
        self.z: C = None
        self.s: C = None
        self.x: D = None
        self.p: C = None
        self.q: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: G = None
        self.y: G = None
        self.s: G = None
        self.q: G = None
        self.w: B = None
        self.u: I = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: H = None
        self.t: C = None
        self.x: E = None
        self.y: H = None
        self.u: A = None
        self.z: F = None
        self.r: C = None
        self.w: H = None
        self.o: A = None
        self.txt = txt

l = A("l")
i = B("i")
j = C("j")
a = D("a")
b = E("b")
k = F("k")
e = G("e")
m = H("m")
n = I("n")

l.r = j
l.q = e
l.t = e
l.y = a
l.v = m
l.o = b
i.o = m
i.t = b
i.x = a
i.p = n
i.w = e
i.q = e
j.q = b
j.p = l
j.u = l
a.q = n
a.y = i
a.v = k
a.z = b
a.r = j
a.o = j
b.u = l
b.o = l
b.t = l
b.r = k
b.p = j
b.z = e
k.v = e
k.o = e
k.z = n
k.p = n
k.x = n
k.u = j
e.o = k
e.r = k
e.z = j
e.s = j
e.p = j
e.x = a
e.q = n
m.z = b
m.r = e
m.y = e
m.s = e
m.q = e
m.w = i
m.u = n
m.p = n
n.v = m
n.y = m
n.w = m
n.t = j
n.r = j
n.x = b
n.u = l
n.o = l
n.z = k
assert n.x.z.p.q.txt == "
class A:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: G = None
        self.y: D = None
        self.v: H = None
        self.t: G = None
        self.o: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.t: E = None
        self.x: D = None
        self.p: I = None
        self.w: G = None
        self.q: G = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.o: G = None
        self.z: I = None
        self.p: I = None
        self.u: C = None
        self.x: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.r: F = None
        self.z: C = None
        self.s: C = None
        self.x: D = None
        self.p: C = None
        self.q: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: G = None
        self.y: G = None
        self.s: G = None
        self.q: G = None
        self.w: B = None
        self.u: I = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: H = None
        self.t: C = None
        self.x: E = None
        self.y: H = None
        self.u: A = None
        self.z: F = None
        self.r: C = None
        self.w: H = None
        self.o: A = None
        self.txt = txt

l = A("l")
i = B("i")
j = C("j")
a = D("a")
b = E("b")
k = F("k")
e = G("e")
m = H("m")
n = I("n")

l.r = j
l.q = e
l.t = e
l.y = a
l.v = m
l.o = b
i.o = m
i.t = b
i.x = a
i.p = n
i.w = e
i.q = e
j.q = b
j.p = l
j.u = l
a.q = n
a.y = i
a.v = k
a.z = b
a.r = j
a.o = j
b.u = l
b.o = l
b.t = l
b.r = k
b.p = j
b.z = e
k.v = e
k.o = e
k.z = n
k.p = n
k.x = n
k.u = j
e.o = k
e.r = k
e.z = j
e.s = j
e.p = j
e.x = a
e.q = n
m.z = b
m.r = e
m.y = e
m.s = e
m.q = e
m.w = i
m.u = n
m.p = n
n.v = m
n.y = m
n.w = m
n.t = j
n.r = j
n.x = b
n.u = l
n.o = l
n.z = k
assert n.x.z.p.q.txt == "b"