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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: C = None
        self.u: E = None
        self.v: D = None
        self.p: E = None
        self.txt = txt

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

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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: C = None
        self.u: E = None
        self.v: D = None
        self.p: E = None
        self.txt = txt

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

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