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

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.z: D = None
        self.x: F = None
        self.y: D = None
        self.u: E = None
        self.t: A = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.y: G = None
        self.t: D = None
        self.u: A = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.z: D = None
        self.x: F = None
        self.y: D = None
        self.u: E = None
        self.t: A = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.y: G = None
        self.t: D = None
        self.u: A = None
        self.txt = txt

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

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

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

i.t = e
i.r = e
i.z = m
i.v = k
i.w = k
i.u = l
i.x = c
c.s = l
c.z = k
c.y = k
c.x = j
c.u = e
c.t = i
m.y = k
m.w = c
m.t = i
m.s = e
k.q = c
k.z = c
k.u = e
e.x = i
e.u = i
e.y = l
e.t = k
j.z = l
j.y = l
j.x = k
j.q = e
j.v = c
j.s = c
l.x = e
l.u = k
l.v = k
assert e.y.v.u.x.u.x.txt == "e"