[learn Python from simple to deep] function 2 user defined function

One 、 Define a nonparametric function

# Define a nonparametric function 
def sayHello():
print("hello")
sayHello() # Call function 

hello

Two 、 Define a function with parameters

# Define a function with parameters 
def myAbs(x):
if x >=0:
return x
else:
return -x

# Call function , Pass in the parameter 
myAbs(4)

4