class A:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: D = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: D = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: A = None
        self.t: B = None
        self.txt = txt

j = A("j")
k = B("k")
i = C("i")
n = D("n")
m = E("m")
f = F("f")
c = G("c")
l = F("l")
b = A("b")
d = D("d")

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

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

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

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: D = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: A = None
        self.t: B = None
        self.txt = txt

j = A("j")
k = B("k")
i = C("i")
n = D("n")
m = E("m")
f = F("f")
c = G("c")
l = F("l")
b = A("b")
d = D("d")

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