Use of else statement result in the following error : SyntaxError: invalid syntax

The even_numbers function returns a space-separated string of all positive numbers that are divisible by 2, up to and including the maximum that's passed into the function. For example, even_numbers(6) returns “2 4 6”.

Furthermore, the else statement gives a syntax error. I can't figure out the issue.

els
def even_numbers(maximum):
    return_string = ""
    for x in range(1,maximum):
        x=x*2
        return_string += str(x) + " "
        if maximum%2==0:
            x == maximum
            break
        else x == maximum:
         break
    return return_string.strip()

print(even_numbers(6))  # Should be 2 4 6
print(even_numbers(10)) # Should be 2 4 6 8 10
print(even_numbers(1))  # No numbers displayed
print(even_numbers(3))  # Should be 2
print(even_numbers(0))  # No numbers displayed
'''