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5 Of The Most Helpful Python List Methods

Aya Bouchiha
Full stack web developer
・2 min read

Hello everybody,
Today we'll discuss 5 helpful Python list methods.

clear()

clear(): This method helps you to delete all list elements.

cities = ['azemmour', 'tanger', 'casablanca']
print(len(cities)) # 3
cities.clear()
print(cities) # []
print(len(cities)) # 0
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reverse()

reverse(): reverse the order of the list's elements.

cities = ['azemmour', 'tanger', 'casablanca']
cities.reverse()

print(cities)  # ['casablanca', 'tanger', 'azemmour']
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copy()

copy(): returns a copy of the specified list.

cities = ['azemmour', 'tanger', 'casablanca']
moroccan_cities = cities.copy()
cities[0] = 'madrid'

print(cities) # ['madrid', 'tanger', 'casablanca']
print(moroccan_cities) # ['azemmour', 'tanger', 'casablanca']
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count(value)

count(): returns the number of repeated items with the given value in a specified list.

product_prices = [12, 227, 0, 54, 0, 20]
free_products_number = product_prices.count(0)

print(free_products_number) # 2
print(product_prices.count(224578)) # 0
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index(value)

index(value): this list method returns the position at the first occurrence of the given value in the specified list.in addition, this method raises an error if the given value does not exist in the specified list.

admins = ['John Doe', 'Aya Bouchiha', 'Simon Heebo']

print(admins.index('Aya Bouchiha')) # 1
print(admins.index('this is not an admin')) # error
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summary

  • clear(): deletes all list's elements.
  • reverse(): reverse the order of the list's elements.
  • copy(): returns a copy of the specified list.
  • count(value): returns the number of repeated items with the given value in a specified list.
  • index(value): returns the position at the first occurrence of the given value in the specified list, and raises an error if the given value is not found.

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