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

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.v: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.p: D = None
        self.v: C = None
        self.y: C = None
        self.r: H = None
        self.w: A = None
        self.o: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.v: H = None
        self.w: F = None
        self.o: B = None
        self.p: C = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.v: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.p: D = None
        self.v: C = None
        self.y: C = None
        self.r: H = None
        self.w: A = None
        self.o: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.v: H = None
        self.w: F = None
        self.o: B = None
        self.p: C = None
        self.txt = txt

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

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

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