An attempt at making an encrypting algo in Python., Python 3

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'''
Example or "What am I aiming for?" 
abcd ----(encrypting) ---> cded (This pattern kind of recognisable here, isn't it?)
dcba ----(encrypting) ---> feda (Don't think this is much similar to the original string. Is it?)
ACEGI ----(encrypting) ---> EGIKI (Not at all similar to the original string. That's a good think.)
James ----(encrypting) ---> xy}s
James Collins ----(encrypting) ---> xy}ęfulrsxs

Seems like we lost a bit of information, but it's actually not the case. The character is their but it's just not rendered.
I have checked it using the 'len()' function on the encrypted version of the string. Also, good on you for noticing that missing character.

There's 1 problem in this program.

Example:
Suppose, the input is: JJJJJ
Guess what output is? Well, the output is: JJJJJ.

Do you see it?
Exactly. It doesn't encrypt the characters that have no difference in their ascii value.
Well, you can't expect too much from a 12 line program.
'''
import math

string = input("Enter your string to be encrypted: ") # Getting the input.
encrypted = "" # Initialising the empty string.
print()

for i in range(len(string) - 1):
    char_encrypt = ord(string[i]) # Getting the ascii value of the current character.
    next_char = ord(string[i + 1]) # Getting the ascii value of the next character.
    diff_val = int(math.fabs(next_char - char_encrypt)) # Calculating the difference in the ascii values.
    req_char = char_encrypt + 2 * diff_val
    encrypted += chr(req_char) # Adding the character into the string.

encrypted += string[-1] # Adding the last character of the string.
print(encrypted)
print(len(encrypted))

# NOTE: Sometimes this program can give ABSOLUTELY fucking weird outputs. Example: Motherfucker ----(encrypting)---> ynswr
# Thank you for checking out my program.
# PROGRAM BY 'JAMES COLLINS'

[ - ] Show input
Absolute running time: 0.17 sec, cpu time: 0.03 sec, memory peak: 8 Mb, absolute service time: 0,31 sec