Finding the index of an item in a list

To find the index of an item in a list in Python, you can use the index() method of the list. This method returns the index of the first occurrence of the item in the list.

Here's an example:

# Define a list of fruits
fruits = ['apple', 'banana', 'mango', 'orange']

# Find the index of 'mango' in the list
index = fruits.index('mango')

# Print the index
print(index)

This will output 2, because 'mango' is the third item in the list and the indices in the list start at 0.

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If the item is not in the list, the index() method will raise a ValueError exception. You can handle this exception by using a try-except block.

# Define a list of fruits
fruits = ['apple', 'banana', 'mango', 'orange']

# Try to find the index of 'grapes' in the list
try:
    index = fruits.index('grapes')
except ValueError:
    index = -1

# Print the index
print(index)

This will output -1, because 'grapes' is not in the list.