turtle won't draw because TypeError: unsupported operand type(s) for -: 'tuple' and 'float'

I'm trying to draw circles given in dictionary dct and then draw lines between the circles names give as tuples in list e .

import turtle
e = [('A','B') , ('A','C') , ('B' , 'C')]
dct = {'A': (250.0, 0.0), 'B': (-125.0, 216.5), 'C': (-125.0, -216.50)}
for x in dct :
    turtle.penup()
    turtle.goto(dct[x][0] , dct[x][1])
    turtle.pendown()
    turtle.circle(20)
    turtle.write(x, move=False, align='left', font='Arial')
    turtle.penup()
for y in range(len(e)) :
    turtle.goto(dct[e[y][0]], dct[e[y][1]])
    turtle.pendown()
    turtle.goto(dct[e[y+1][0]], dct[e[y+1][1]])
    turtle.penup()

but it gives me long error the end of it is :

  File "/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/turtle.py", line 1777, in goto
    self._goto(Vec2D(x, y))
  File "/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/turtle.py", line 3166, in _goto
    diff = (end-start)
  File "/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/turtle.py", line 263, in __sub__
    return Vec2D(self[0]-other[0], self[1]-other[1])
TypeError: unsupported operand type(s) for -: 'tuple' and 'float'

Just change your second loop like so:

import turtle
e = [('A','B') , ('A','C') , ('B' , 'C')]
dct = {'A': (250.0, 0.0), 'B': (-125.0, 216.5), 'C': (-125.0, -216.50)}
for x in dct :
    turtle.penup()
    turtle.goto(dct[x][0] , dct[x][1])
    turtle.pendown()
    turtle.circle(20)
    turtle.write(x, move=False, align='left', font='Arial')
    turtle.penup()
for y in range(len(e)) :
    turtle.goto(dct[e[y][0]][0], dct[e[y][0]][1])
    turtle.pendown()
    turtle.goto(dct[e[y][1]][0], dct[e[y][1]][1])
    turtle.penup()

Instead of:

turtle.goto(dct[e[y][0]], dct[e[y][1]])

and

turtle.goto(dct[e[y+1][0]], dct[e[y+1][1]])

You needed:

turtle.goto(dct[e[y][0]][0], dct[e[y][0]][1])

and

turtle.goto(dct[e[y][1]][0], dct[e[y][1]][1])