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

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.y: G = None
        self.p: A = None
        self.z: E = None
        self.q: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.u: B = None
        self.r: A = None
        self.o: C = None
        self.x: F = None
        self.v: E = None
        self.txt = txt

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

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

k.o = i
c.t = j
c.y = j
c.p = k
c.z = a
c.q = m
e.v = a
l.y = e
l.u = e
a.z = b
a.u = b
a.x = j
a.v = j
b.p = e
b.o = e
b.u = c
b.r = k
b.x = m
b.v = a
j.t = l
i.o = k
m.p = e
m.o = e
m.u = c
m.r = i
m.x = b
m.v = a
assert e.v.z.u.y.t.u.v.x.t.txt == "
class A:
    def __init__(self, txt: str):
        self.o: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.y: G = None
        self.p: A = None
        self.z: E = None
        self.q: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.u: B = None
        self.r: A = None
        self.o: C = None
        self.x: F = None
        self.v: E = None
        self.txt = txt

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

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

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