Using .lower or 'or' in if __ is __ statement causes incorrect if statement flow in python 3.6

I searched and couldn't seem to find anyone who has had this same issue, although I'm very new to python and there's a great chance it is just user error.

I'm having problems using both 'or' and .lower in an if statement. If i use the code:

print('press Y to continue or Q to quit')
end = input()
if end is 'y':
    continue
else:
    break

then my code works correctly, although if the user types in a capital Y, the program continues to the else statement, and ends the program. If I use the following code:

print('press Y to continue or Q to quit')
end = input()
end = end.lower
if end is 'y': #I have also tried end.lower here, removing the line above
    continue
else:
    break

The program continues to break with any input. If I print 'end' before the if statement, it returns:

<built-in method lower of str object at 0x7fa6b8176f80>

Seeing that this wasn't working for me, I tried this:

print('press Y to continue or Q to quit')
end = input()
if end is 'y' or 'Y':
    continue
else:
    break

which causes any input to continue, even if I define a specific key to break using elif.

I've seen both of these methods suggested to accept either two inputs or make 'end' lowercase on this site. I've also tried replacing is with ==, which gives me the same results. Is there a problem with how I'm phrasing my if is statement?