Ggtcf

This is my code for pictograph.
I want it to be like John = * * * * *
and why is there a "None" in the output?

print("Pictograph")
def J(a):
 for i in range(1, a+1):
 print("*", end=" ")
def C(b):
 for j in range(1, b+1):
 print("*", end=" ")
def Z(c):
 for j in range(1, c+1):
 print("*", end=" ")
x = int(input("Enter John's Number: "))
y = int(input("Enter Chas's Number: "))
z = int(input("Enter Zed's Number: "))

print("John = ", J(x))
print("Chas = ", C(y))
print("Zed = ", Z(z))

and this is the output

Pictograph
Enter John's Number: >? 5
Enter Chas's Number: >? 4
Enter Zed's Number: >? 3
* * * * * John = None
* * * * Chas = None
* * * Zed = None

You are defining a function from which you are returning nothing. Change your functions to return a value. Also, did you know that you can repeat a string using the * operator, for example 3 * 'a' is 'aaa':

def J(a):
 return (a * '* ')[:-1]

s[:-1] means you are taking all the elements of a string s but the last one.

You can also define a function to print your pattern, so you avoid code repetition.

def repeat_pattern(n):
 return (n * '* ')[:-1]

Therefore, your code will be as follows:

print("Pictograph")
x = int(input("Enter John's Number: "))
y = int(input("Enter Chas's Number: "))
z = int(input("Enter Zed's Number: "))
print("John =", repeat_pattern(x))
print("Chas =", repeat_pattern(y))
print("Zed =", repeat_pattern(z))

The whole code could be just:

print("Pictograph")
x = int(input("Enter John's Number: "))
y = int(input("Enter Chas's Number: "))
z = int(input("Enter Zed's Number: "))
print("John =", ' '.join(x * '*'))
print("Chas =", ' '.join(y * '*'))
print("Zed =", ' '.join(z * '*'))

Or like @lmiguelvargasf's solution:

print("Pictograph")
x = int(input("Enter John's Number: "))
y = int(input("Enter Chas's Number: "))
z = int(input("Enter Zed's Number: "))
print("John =", (x * '* ')[:-1])
print("Chas =", (y * '* ')[:-1])
print("Zed =", (z * '* ')[:-1])

Both reproduce this (example output):

Pictograph
Enter John's Number: 5
Enter Chas's Number: 4
Enter Zed's Number: 3
John = * * * * *
Chas = * * * *
Zed = * * *

Since you're familar with loops, I would go with a solution that lets you add more data without having to add more code:

print("Pictograph")

data = []

for person in ['John', 'Chas', 'Zed']:
 data.append((person, int(input(f"Enter person's Number: "))))

for person, number in data:
 print(f"person =", *(['*'] * number))

USAGE

> python3 test.py
Pictograph
Enter John's Number: 13
Enter Chas's Number: 3
Enter Zed's Number: 20
John = * * * * * * * * * * * * *
Chas = * * *
Zed = * * * * * * * * * * * * * * * * * * * *
>

You might consider a tab character in the output to align the left-most stars.