class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.u: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: F = None
        self.u: A = None
        self.p: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.x: D = None
        self.s: C = None
        self.p: C = None
        self.z: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: E = None
        self.q: E = None
        self.t: C = None
        self.p: D = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: F = None
        self.u: A = None
        self.p: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.x: D = None
        self.s: C = None
        self.p: C = None
        self.z: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: E = None
        self.q: E = None
        self.t: C = None
        self.p: D = None
        self.txt = txt

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

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

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