Russ Maxwell's Blog

Python Lists Cheat Sheet

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russmaxwell

–

I created a cheat sheet to help when working with common python data types like dictionaries, lists, strings, and tuples.  Knowing how to work with these data types will accelerate your Python development skillset.  I hope you find this useful.

Create Lists and store different datatypes

##Create a List of strings##
names = ['Russ', 'Jon', 'Mike', 'Dan']

##Create a list of strings and numbers##
names_ages = ['Russ',45,'Jon', 44, 'Mike',48,'Dan',46]
    
##List containing strings and lists##
carcontainsmileage = ['mustang',[42858], 'bronco',[2300], 'suburban',[35888]]
    
##list containing dictionaries##
names_ages_dict = [{'Russ':45,'Jon':44},{'Mike':48, 'Dan':46}]
    
##list containing tuples##
names_ages_tupl = [('Russ',45),('Jon',44),('Mike',48),('Dan',46)]

Access Items within a List

names = ['Russ', 'Jon', 'Mike', 'Dan']
    
#option 1
print(names.__getitem__(2))

output: 'Mike'

#option2
print(names[2])

output: 'Mike'
    
#option 3: 

for n in names:
    print(n)
    
    output: Russ
            Jon
            Mike
            Dan

Update a List 

names = ['Russ', 'Jon', 'Mike', 'Dan']
    
##Append string to end of list##
names.append('Jeff')
print(names)

Output: ['Russ', 'Jon', 'Mike', 'Dan', 'Jeff']
    
##Remove the first name from the existing list##
names.remove(names[0])

output: ['Jon','Mike','Dan']

Combine multiple lists into a single list

names1 = ['Russ', 'Jon']
names2 = ['Mike', 'Dan']
       
names = names1 + names2

output: ['Russ', 'Jon', 'Mike', 'Dan']

Convert different datatypes to a list

##Convert tuple to list##
mytuple = (1,2,3)
mylist = list(mytuple)
    
output: [1, 2, 3]
    
##Convert string to list##
namestr = 'russmax'
namelst = list(namestr)
    
output: ['R', 'u', 's', 's', 'm', 'a', 'x']
    
##Convert dictionary to list##
namedict = {'first':'russ','last':'max'}
names = list(namedict.items())
    
output: [('first', 'russ'), ('last', 'max')]

I created a simple python program to provide these details as help content in addition to other data types.

https://github.com/RussMaxwell/PythonHelper

Python Cheat Sheet Series

Thank You,

Russ Maxwell