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

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: E = None
        self.u: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.r: G = None
        self.y: A = None
        self.o: F = None
        self.w: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: F = None
        self.t: F = None
        self.u: A = None
        self.v: G = None
        self.z: E = None
        self.x: B = None
        self.p: E = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: E = None
        self.u: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.r: G = None
        self.y: A = None
        self.o: F = None
        self.w: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: F = None
        self.t: F = None
        self.u: A = None
        self.v: G = None
        self.z: E = None
        self.x: B = None
        self.p: E = None
        self.txt = txt

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

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

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