Python Search, Clear

To detect do we have specific element in list we can use simple if statement - this is "yes or no" situation:

names =["Michael", "Samantha", "Anastasia", "John"]

if "Samantha" in names:
    print("Samantha is there")

Result: 

Samantha is there
>>> 

What if Samantha is not element of list:

names =["Michael", "Anastasia", "John"]

if "Samantha" in names:
    print("Samantha is there")
else:
    print("Samantha is not there")

Result: 

Samantha is not there
>>> 

If we create multiple lists based on one original list, all changes will replicate to those lists, too:

names =["Michael", "Samantha", "Anastasia", "John"]

a = names
b = names
c = names

names[0] = "New Name"
print(names)
print()
print(a)
print(b)
print(b)

Result: 

['New Name', 'Samantha', 'Anastasia', 'John']

['New Name', 'Samantha', 'Anastasia', 'John']
['New Name', 'Samantha', 'Anastasia', 'John']
['New Name', 'Samantha', 'Anastasia', 'John']
>>> 

To delete all elements, there's dedicated clear() function:

names =["Michael", "Samantha", "Anastasia", "John"]

names.clear()
print(names)

Result: 

[]
>>> 

To delete whole list, use del() function:

names =["Michael", "Samantha", "Anastasia", "John"]

#List destruction
del names

You can't print from something you destroyed:

names =["Michael", "Samantha", "Anastasia", "John"]

del names
print(names)

Result: 

Traceback (most recent call last):
  File "C:\Python38-64\ARCHIVE\learning-python.py", line 4, in <module>
    print(names)
NameError: name 'names' is not defined
>>> 

In next tutorial, we will learn about Tuples.