def add_is_prefix(input_string):
# Check if the string already starts with "Is"
if input_string.startswith("Is"):
return input_string
else:
# Add "Is" to the front of the string
return "Is" + input_string
# Example usage:
print(add_is_prefix("Island")) # Output: Island
print(add_is_prefix("land")) # Output: Island
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