The task is to reverse a given string without utilizing any built-in methods in Python. For instance, if the input string is “hello”, the expected output should be “olleh”. 

def reverse_string(input_string):
    reversed_string = ""
    for char in input_string:
        reversed_string = char + reversed_string
    return reversed_string

# Example usage
input_str = "hello"
output_str = reverse_string(input_str)
print(output_str)  # Output: "olleh"

Another efficient way to reverse a string in Python is by using slicing. Here is a simple and efficient way to do it –

# Original string
original_string = "Hello, World!"

# Reversed string using slicing
reversed_string = original_string[::-1]

print(reversed_string)

This method uses Python’s slicing feature, where [::-1] means “take the string and step backward by 1.” It’s concise and performs very well.