Incorrectly counting parameters?

Question

Why does it say I passed one argument when nothing is between the parentheses?

class mammal:
def __init__(self, legs, eyes, hasFur):
print("Creating a new mammal with",legs,"legs and",eyes,"eyes.")
self.legs = legs
self.eyes = eyes
self.hasFur = hasFur
self.liveBirth = True
def makeNoise():
print("Mammal makes a noise")
def addEyes(num):
self.eyes += num
def showData():
print("legs:",self.legs)
print("eyes:",self.eyes)
dog = mammal(4, 2, True)
human = mammal(2, 2, False)
alien = mammal(3, 10, False)

human.showData()

Answer 1

define showData () as :=>

def showData( self ) :

Answer 2

Each method(function of a class) must have at least 1 parameter (conventionally named "self") that refers to the class itself.
https://code.sololearn.com/cmA01N8YPBqW/?ref=app