FAQ: Learn Python - Classes - Building useful classes

This community-built FAQ covers the “Building useful classes” exercise in Codecademy’s lessons on Python.

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i couldnt guess this part: my_point = Point3D(1, 2, 3)

ithough as the instructions says to asign to x, y, z, like my_point.Point3D(x =1, y=2, z =3) somethings i find really difficult to guess… :frowning:


Thats my code, that shows the error message "it looks like you didn’t print “(1,2,3)”. For me is the same that is in the solution. What is wrong?

class Point3D(object):
def init(self,x,y,z):

def repr(self):
return “(%d,%d,%d)” % (self.x,self.y,self.z)

my_point = Point3D(1,2,3)
print my_point

class Point3D(object):
  def __init__(self, x, y, z):
    self.x = x
    self.y = y
    self.z = z
  def __repr__(self, x, y, z):
    return "( %d, %d, %d )" % (str(self.x), str(self.x), str(self.x))
my_point = Point3D(1, 2, 3)
print my_point

dont understand error…

Traceback (most recent call last):
File “python”, line 9, in
TypeError: repr() takes exactly 4 arguments (1 given)

class Point3D(object):
  def __init__(self, x, y, z):
    self.x = x
    self.y = y
    self.z = z
  def __repr__(self):
    return "( %s, %s, %s )" % (str(self.x), str(self.y), str(self.z))
my_point = Point3D(1, 2, 3)
print my_point

got it now works perfect

1 Like