class A:
    def __init__(self, txt: str):
        self.o: I = None
        self.r: H = None
        self.w: C = None
        self.t: G = None
        self.z: H = None
        self.q: I = None
        self.x: C = None
        self.s: F = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.o: I = None
        self.p: H = None
        self.z: E = None
        self.s: G = None
        self.r: F = None
        self.y: F = None
        self.t: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: I = None
        self.u: H = None
        self.y: B = None
        self.q: E = None
        self.p: E = None
        self.z: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.q: C = None
        self.z: B = None
        self.t: D = None
        self.o: D = None
        self.w: F = None
        self.p: D = None
        self.u: B = None
        self.r: A = None
        self.txt = txt

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

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

i = A("i")
c = B("c")
d = C("d")
n = D("n")
e = E("e")
b = F("b")
j = G("j")
l = H("l")
m = I("m")
g = I("g")

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: I = None
        self.p: H = None
        self.z: E = None
        self.s: G = None
        self.r: F = None
        self.y: F = None
        self.t: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: I = None
        self.u: H = None
        self.y: B = None
        self.q: E = None
        self.p: E = None
        self.z: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.q: C = None
        self.z: B = None
        self.t: D = None
        self.o: D = None
        self.w: F = None
        self.p: D = None
        self.u: B = None
        self.r: A = None
        self.txt = txt

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

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

i = A("i")
c = B("c")
d = C("d")
n = D("n")
e = E("e")
b = F("b")
j = G("j")
l = H("l")
m = I("m")
g = I("g")

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