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

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

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.w: D = None
        self.u: F = None
        self.v: G = None
        self.o: G = None
        self.r: B = None
        self.q: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.s: A = None
        self.q: A = None
        self.v: F = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: A = None
        self.t: B = None
        self.u: D = None
        self.s: C = None
        self.v: D = None
        self.o: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

l = A("l")
j = B("j")
h = C("h")
m = D("m")
f = E("f")
g = F("g")
e = G("e")
i = D("i")
d = A("d")

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

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

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.w: D = None
        self.u: F = None
        self.v: G = None
        self.o: G = None
        self.r: B = None
        self.q: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.s: A = None
        self.q: A = None
        self.v: F = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: A = None
        self.t: B = None
        self.u: D = None
        self.s: C = None
        self.v: D = None
        self.o: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

l = A("l")
j = B("j")
h = C("h")
m = D("m")
f = E("f")
g = F("g")
e = G("e")
i = D("i")
d = A("d")

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