How to Append String to Beginning of List Python | How to Append to Start of String Python

In this Python tutorial, I will explain how to append string to beginning of list Python using some methods. I will explain some examples related to all the methods.

I will also explain, how to append to start of string Python using some methods in Python with the help of some demonstrative examples.

Appending a string to the beginning of a list in Python can be done using various methods. Lists are versatile data structures that allow for flexible manipulation of data, and adding a string to the beginning is a common operation. In this article, we’ll explore several methods to achieve this task, from basic techniques to more advanced ones.

Methods to append string to beginning of list Python

There are many different methods present in Python to append a string to the beginning of the list.

• The insert() Method
• The List Concatenation
• The List Slicing
• The * Operator (Unpacking)
• The Deque from the Collections Module
• extend() Method with a Reversed List
• append() Method

Let’s see them one by one using some demonstrative examples:

Method 1: Python string append to front of a list using insert() function

For the built-in insert() method for lists in Python, we specify the index where we want to add the new element (in this case, a string), and it shifts the existing elements to accommodate the new one. In our case, we insert the string at index 0 (positive index), effectively adding it to the beginning of the Python list.

Syntax:

my_list.insert(index, element)

Name	Description
my_list	This is the list on which we want to perform the insertion.
index	It represents the position in the list where the element will be added.
element	This is the element we want to insert into the list at the specified index.

Example: Consider a situation where we have a list of data in alphabetical order, and we want to insert new data, at the beginning of the list because it’s the first alphabetically.

us_states = ["Alaska", "Arizona", "California", "Colorado"]
us_states.insert(0, "Alabama")
print(us_states)

Output: In this example, we use the insert() function to insert the Python string at the beginning of the list (0 is the index), shifting the existing elements to make room in the Python List.

['Alabama', 'Alaska', 'Arizona', 'California', 'Colorado']

This way we can use the insert() function to append string to beginning of list Python.

Method 2: Add string to beginning of list Python using list concatenation

Here, we create a new list by joining two Python lists using the + operator. The first list is the one with the string we want to add to the beginning, and the second list is the original Python list. This method does not modify the original Python list but produces a new one with the desired change.

Scenario: Suppose we have a list in Python, and we need to add one string to the beginning of that Python list.

us_cities = ["Los Angeles", "Chicago", "Houston"]
new_us_cities = ["New York City"] + us_cities
print(new_us_cities)

Output: In this example, we are first creating a list of the Python string that we want to append and then adding both the Python list with the help of the + operator in Python.

['New York City', 'Los Angeles', 'Chicago', 'Houston']

We can use a + operator and [] operator to append string to beginning of list Python.

Method 3: Python append to start of list using slicing

The List slicing can select a portion of the list starting from the beginning (index 0) and ending just before index 0. Essentially, it selects an empty slice at the very beginning of the list in Python.

Syntax:

list[start:end:step]

Name	Description
start	It is the index where the slice begins in Python (inclusive).
end	It is the index where it ends (exclusive).
step	It is the step size for selecting elements in Python (optional, defaults to 1)

Example: Consider a situation where we have a list and we want to add a new element as a Python string at the beginning of the list.

usa_cities = ["New York","Los Angeles", "Chicago"]
usa_cities[:0] = ["Dallas"]
print(usa_cities)

Output: Here, we have created a space at the beginning of the Python list and then assigned that space our string. And, we have successfully append string to beginning of list Python.

['Dallas', 'New York', 'Los Angeles', 'Chicago']

This way we can use list slicing in the Python list to append a string in the beginning.

Method 4: how to add an item to the start of a list in Python using the * (unpack) operator

The * operator is used to unpack the elements of the original list and add them to a new list. By placing the string we want to prepend before the * operator, we create a new list that includes the desired element at the beginning.

Scenario: Let’s consider a situation where we have a list, and we need to add a string to the beginning of it. We will use the * operator to do so.

us_airlines = ["American Airlines", "United Airlines", "Southwest Airlines"]
new_us_airlines = ["Delta Air Lines", *us_airlines]
print(new_us_airlines)

Output: Here, in this example, we are creating a new list in Python with the string at the beginning of the list and then adding the existing list by unpacking the list with the help of the * operator.

['Delta Air Lines', 'American Airlines', 'United Airlines', 'Southwest Airlines']

This way we can use the * operator to append string to beginning of list Python.

Method 5: Add a string to beginning of list Python using deque from the collections Module

In this method, we use the deque (double-ended queue) data structure from the collections module. Deques allow for efficient appending and popping from both ends. We use the appendleft() method of the deque to add the Python string to the beginning.

For instance: We’re maintaining a Python list, and we want to add a string to the beginning of the list.

from collections import deque

us_time_zones = deque(["Central Time", "Mountain Time", "Pacific Time"])
us_time_zones.appendleft("Eastern Time")
print(us_time_zones)

Output: The appendleft(string) adds the string to the beginning of the deque list using the appendleft() method in Python.

deque(['Eastern Time', 'Central Time', 'Mountain Time', 'Pacific Time'])

This way we can the deque from the collections module to append string to beginning of list Python.

Method 6: Python add a string to start of the list using extend() function

In Python, the extend() method is typically used to append multiple elements from an iterable (like a list, tuple, or string) to the end of an existing Python list. It is not used to append elements to the beginning of a list. But, if we want to add a single element (e.g., a string) to the beginning of a Python list, we can do the following way:

Example: In our Python list, we want to add a string to the beginning for some reason.

us_time_zones = ["Eastern Time", "Central Time", "Mountain Time"]
all_time_zones = ["Hawaii-Aleutian Time"]
all_time_zones.extend(us_time_zones)
print(all_time_zones)

Output: In this method, we are extending the string at the beginning of the list in Python using the extend() method.

['Hawaii-Aleutian Time', 'Eastern Time', 'Central Time', 'Mountain Time']

This way we can use the extend() method to add a string to the beginning of the list in Python.

Method 7: Python append to start of list using append() function

Similar to the extend() function we use the append() function to append elements to the end of a list. But, to add or append string to beginning of list Python using the append() function, we can do it this way:

Example: In our list in Python of a sequence, we need to prepend a name that should come at the beginning of the sequence.

us_presidents = ["John Adams", "Thomas Jefferson", "James Madison"]
correct_sequence = ["George Washington"]
for item in us_presidents:
    correct_sequence.append(item)
print(correct_sequence)

Output: In this case, we have created a list of one element from the Python string that we have to append at the beginning of the list. Then, we use a for loop to iterate over the existing Python list and append each element from that list to the newly created list in Python.

['George Washington', 'John Adams', 'Thomas Jefferson', 'James Madison']

This way we can append string to beginning of list Python using the append() function.

So, these were the seven methods that I came across while my research to append string to beginning of list Python. Now, let’s go about how to append a string to the start of a string in Python.

Methods to append to start of string Python

There are many different methods to append to start of string Python:

• The + Operator
• Using String Formatting
• Using f-Strings (Python 3.6+)
• Using str.join()

Let’s see them one by one using some demonstrative examples:

Method 1: Python add to start of string using the + operator

The + operator simply combines two Python strings together by placing one in front of the other.

Example: Consider, that we have a question to give answers in one word as a Python string, and want the answer to be added to the start of the string in Python, so let’s do it using the + operator.

original_sentence = "is known for its national parks."
state_name = "California"
result = state_name + " " + original_sentence
print(result)

Output: Here, we are concatenating both the Python strings using the + operator.

California is known for its national parks.

This way we can use the + operator to append to start of string Python

Method 2: Python add to beginning of string using string formatting

The string formatting uses placeholders {} within a template string, and str.format() replaces them with specified values. We can prepend a Python string by including both the new and original strings in the format method in Python.

For instance: We have two different strings in Python and have to add one string at the start of the other one, but have to use Python string formatting.

landmark = "Statue of Liberty"
sentence_template = "{} is a symbol of freedom."
result = sentence_template.format(landmark)
print(result)

Output: Here, we have first initialize a placeholder {} to the starting of the string in Python in which we have to append another string to and then we use format() to append the other string.

Statue of Liberty is a symbol of freedom.

This way we can use string formatting to append a string start of another string in Python.

Method 3: Append to start of string Python using f-Strings

The f-strings, introduced in Python 3.6, allow us to prepend a string by enclosing it in curly braces {} within a string prefixed with ‘f‘.

Example: In this case, we will use an f-string to insert the Python string into the starting of a sentence, which is also a Python string.

capital = "Washington, D.C."
sentence = f"{capital} is the capital of the USA."
print(sentence)

Output:

Washington, D.C. is the capital of the USA.

The f-string in Python can be used this way to append to start of string Python.

Method 4: Add string to beginning of string Python using str.join() function

The str.join() concatenates a list of strings in Python, including the one we want to prepend. It’s useful for combining multiple strings efficiently without any delimiter through Python.

Scenario: Consider a situation where, we have a list in Python containing different strings, and we have to append another Python string at the beginning of them and get the output as a Python string. We will use the Python join() function to do so.

neighboring_states = ["New York", "New Jersey", "Connecticut"]
result = ", ".join(["Pennsylvania"] + neighboring_states)
print(result)

Output: Here, we are joining all the strings from the list in Python along with the string at first with the help of the join() function.

Pennsylvania, New York, New Jersey, Connecticut

This way we can use the str.join() method to append a string to the start of another Python string.

These were the four methods I came across to append a string to start of string in Python.

Conclusion

We have learned about how to append string to beginning of list Python using different approaches or methods such as using the insert(), list concatenation with the + operator, List slicing, the * operator (unpacking), deque() method from the collections module, extend() method, and append() method.

We have also learned about how to append to start of string Python using different methods such as the + operator, the string formatting method, using f-strings, or using the str.join() method.

These all methods are explained with the help of some illustrative examples. Each of these methods has its advantages and use cases, so choose the one that best suits one specific needs.

You may like the following Python tutorials:

• How to Reverse a List in Python
• Python dictionary of lists
• Python string to list
• Append meaning