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# Python Count Occurrences in list

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## Glance about ‘List’

A list is a collection of items, which can be of different data types, including numbers, strings, and other objects in python. Lists are defined using square brackets ‘`[]`‘ and items are separated by commas. Lists are mutable, meaning the elements within the list can be changed.

Example:

Python
``````a = [1, 2, 3, 4, 5]
b = ["apple", "banana", "cherry"]
c = [1, "apple", 3.14, True]
``````

## To count how many times an item appears on a list

In Python, you can use the ‘`list.count()`‘ method to count the number of times an item appears in a list.

Example:

Python
``````a = [1, 2, 3, 1, 2, 3, 4, 5, 6, 1]
count = a.count(1)
print(count)
``````

Output:

``3``

You can also use a for loop and an if statement to check each element in the list and increment a counter for each match.

Example:

Python
``````a = [1, 2, 3, 1, 2, 3, 4, 5, 6, 1]
count = 0
for i in a:
if i == 1:
count += 1
print(count)
``````

Output:

``3``

## Repeat items in a list

You can repeat items in a list in Python using the multiplication operator ‘`*`‘ or list comprehension.

To repeat an item using the multiplication operator, you simply multiply the item by an integer. Here’s an example:

Python
``````my_list = ['apple'] * 3
print(my_list)  ``````

Output:

``'apple', 'apple', 'apple'``

In this example, we have a list ‘`my_list`‘ containing a single string `'apple'`. We use the multiplication operator ‘`*`‘ to repeat the string three times, resulting in a new list with three strings.

You can also use list comprehension to repeat an item. Here’s an example:

Python
``````my_list = ['apple' for _ in range(3)]
print(my_list)
``````

Output:

``'apple', 'apple', 'apple'``

In this example, we use list comprehension to create a new list with three strings `'apple'`. The ‘`for`‘ loop in the list comprehension iterates three times, creating a new string `'apple'` on each iteration.

Both of these methods can be used to repeat any item in a list, not just strings. For example, you could repeat numbers, boolean values, or even other lists.

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