Python create list from two strings

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    Given n strings, the task is to merge all strings into a single list.

    While developing an application, there come many scenarios when we need to operate on the string and convert it as some mutable data structure, say list. There are multiple ways we can convert strings into list based on the requirement. Let’s understand it better with help of examples.


    Method #1: Using ast

    import ast

    str1 ="'Geeks', 'for', 'Geeks'"

    str2 ="'paras.j', 'jain.l'"

    str3 ="'india'"

    list = []

    for x in [str1, str2, str3]:

        list.extend[ast.literal_eval[x]]

    print[list]

    Output:

    ['Geeks', 'for', 'Geeks', 'paras.j', 'jain.l', 'i', 'n', 'd', 'i', 'a']
    


    Method #2: Using eval

    str1 ="['Geeks', 'for', 'Geeks']"

    str2 ="['paras.j', 'jain.l']"

    str3 ="['india']"

    out = [str1, str2, str3]

    out = eval['+'.join[out]]

    print[out]

    Output:

    ['Geeks', 'for', 'Geeks', 'paras.j', 'jain.l', 'india']
    

    str1 ="'Geeks', 'for', 'Geeks'"

    str2 = "'121', '142'"

    str3 ="'extend', 'India'"

    out = [str1, str2, str3]

    out = eval['+'.join[out]]

    print[list[out]]

    Output:

    ['Geeks', 'for', 'Geeks121', '142extend', 'India']
    


    This post describes how to work with lists of strings in Python. Lists are one of the most common data structures in Python, and they are often used to hold strings.

    Quick examples

    First we'll give some quick examples:

    # define a list of strings
    >>> names = ["Eve", "Alice", "Bob"]
    
    # print the list of strings
    >>> print[names]
    ['Eve', 'Alice', 'Bob']
    
    # loop over the names list, and
    # print each string one at a time
    >>> for name in names:
    >>>     print[name]
    Eve
    Alice
    Bob
    
    # add a name to the list
    >>> names.append["Charlie"]
    
    # check if the list contains a string
    >>> if "Bob" in names:
    >>>     print["Bob is here"]
    Bob is here
    
    # add another string list to it
    >>> more_names = ["Ivan", "Gerth"]
    >>> names = names + more_names
    
    # sort the list
    >>> names.sort[]
    
    # join the strings in the list by a comma
    >>> comma_separated = ", ".join[names]
    
    >>> print[comma_separated]
    Alice, Bob, Charlie, Eve, Gerth, Ivan
    

    The next sections describe these operations on string lists in more detail.

    Create list of strings

    To create a list of strings, first use square brackets [ and ] to create a list. Then place the list items inside the brackets separated by commas. Remember that strings must be surrounded by quotes. Also remember to use = to store the list in a variable.

    So we get something like this:

    colors = ["red", "blue", "green"]
    

    It is also allowed to put each string on a separate line:

    animals = [
        "deer",
        "beaver",
        "cow"
    ]
    

    Add strings to list

    When you already have a list of strings and you want to add another string to it, you can use the append method:

    colors = ["red", "blue", "green"]
    colors.append["purple"]
    

    You can also create a new list with only one string in it and add it to the current list:

    colors = colors + ["silver"]
    

    Print list of strings

    To print a whole list of strings in one line, you can simply call the built-in print function, giving the list as an argument:

    colors = ["red", "blue", "green"]
    print[colors]
    

    Print list as string

    If you want to convert a list to a string, you can use the built-in function repr to make a string representation of the list:

    products = ["shelf", "drawer"]
    products_as_string = repr[products]
    print[products_as_string]
    

    Concatenate lists of strings

    You can use the + operator to concatenate two lists of strings. For example:

    colors1 = ["red", "blue"]
    colors2 = ["purple", "silver"]
    concatenated = colors1 + colors2
    

    Check if string is in list

    You can use the in keyword to check if a list contains a string. This gives you a boolean value: either True or False. You can store this value somewhere, or use it directly in an if statement:

    colors = ["pink", "cyan"]
    if "pink" in colors:
        print["yes!"]
    
    has_cyan = "cyan" in colors
    print[has_cyan]
    

    Sort list of strings

    To sort a list of strings, you can use the sort method:

    numbers = ["one", "two", "three", "four"]
    numbers.sort[]
    

    You can also use the sorted[] built-in function:

    numbers = ["one", "two", "three", "four"]
    numbers = sorted[numbers]
    

    Join list of strings

    To join a list of strings by another string, you need to call the join method on the string, giving your list as an argument. For example, if we have this list:

    colors = ["red", "blue", "green"]
    

    Then calling:

    print[", ".join[colors]]
    

    Will output:

    red, blue, green
    

    And similarly, print["|".join[colors]] will output:

    red|blue|green
    

    Conclusion

    Being able to manipulate lists of strings is crucial for Python programmers. We've described ways to create, modify, print, sort, and join lists of strings in Python.

    How do I make a list of two strings in Python?

    To create a list of strings in Python, add comma-separated strings inside of square brackets. Remember to add double quotation marks around each string. You can also declare the list of strings using multiple lines. Sometimes the expression is more readable this way.

    How do you make two strings into a list?

    How to Convert a String to a List of Words.
    string is the given string you want to turn into a list..
    The split[] method turns a string into a list. It takes two optional parameters..
    separator is the first optional parameter, and it determines where the string will split. ... .
    maxsplit is the second optional parameter..

    How do I make a list of strings?

    To create a list of strings, first use square brackets [ and ] to create a list. Then place the list items inside the brackets separated by commas. Remember that strings must be surrounded by quotes. Also remember to use = to store the list in a variable.

    How do you make a list of words from a string in Python?

    To convert a string in a list of words, you just need to split it on whitespace. You can use split[] from the string class. The default delimiter for this method is whitespace, i.e., when called on a string, it'll split that string at whitespace characters.

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