Tips for Using format() Function - indexError

When using the format() function, if the number of curly braces ({}) in the string does not match the number of arguments passed to it, an IndexError will occur.

An IndexError occurs when there are more curly braces in the string than arguments, causing the function to fail to map a value to each placeholder.

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greeting = "Hello, {0}! Today is {1}. {2}"

try:
    formatted_greeting = greeting.format("CodeFriend", "Tuesday")
    print(formatted_greeting)

except IndexError as e:
    print(f"Error occurred: {e}")

To prevent indexError, ensure the number of curly braces in the string matches the number of parameters passed to the format() function.

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# Remove {2} to resolve the indexError
greeting = "Hello, {0}! Today is {1}."
formatted_greeting = greeting.format("Chris", "Tuesday")

print(formatted_greeting)  # "Hello, Chris! Today is Tuesday."