Exciting things you can do on Python Lists

#python program to check how many times a number
#appears in a list

def checksomething(lis):
    """This function receives a list
    and returns number of times an
    element appears in a list"""
    lis2=[] #declare an empty list
    for item in lis:
        """This for loop will append element from lis
        to lis2 if the element in an iteration is not
        present in lis2

        The objective is to create another list with
        only unique elements from the main list elements
        """
        if item not in lis2:
            lis2.append(item)

    for item in lis2:
        """This for loop checks the number of times
        an element from lis2 appears in the original list"""
        n=lis.count(item)
        if n==1:
            print("{} appears {} time in the list".format(item,n))
        elif n>=1:
            print("{} appears {} times in the list".format(item,n))
        else:
            print("Thank you!")

#declares a list with elements
list1 = [4,2,2,2,1,1,3,3,4,5,5,5,7,8,9,10]
checksomething(list1) #pass list1 to checksomething function

#Python program to find
#common elements in two lists

def commoninlist(lis1,lis2):
    """This function takes two lists as parameters,
    converts them into sets, so that intersection 
    can be performed to obtain the common elements.
    The final set is again converted to a list"""
    set1=set(lis1) #converts lis1 into a set, set1
    set2=set(lis2) #converts lis2 into a set, set2
    commonset=set1.intersection(set2) #finding common elements and storing into a new set, commonset
    result_list=list(commonset) #converting the set, commonset into a list
    result_list.sort() #sorting the list
    print("The common elements are: ",result_list) #printing the output

list1=[11,22,33,44,77,88,99] #declare list1
list2=[12,33,55,77,88,99] #declare list2

commoninlist(list1,list2) #pass list1 and list2 to commonlist function

#Python program to store and retrieve
#different kinds of datatypes

def differentelements():
    """This function stores different vegetables,
    their prices and discounts into a list and
    finally retrieves one of them into output"""

    n=int(input("How many vegetables do you want to enter?"))
    veg_list=[]
    for item in range(n):
        """This for loop stores vegetables to the
        list, veg_list"""
        print("Enter vegetable name: ",end=" ")
        veg_list.append(input())
        print("Enter price: ",end=" ")
        veg_list.append(int(input()))
        print("Enter max. discount: ",end=" ")
        veg_list.append(float(input()))
    
    print("The complete list with vegetable name: \n",veg_list)

    #Let us now retrieve details of any one vegetable

    veg_name=input("Please enter the vegetable name: ")
    flag=True
    while True:
        if veg_name in veg_list:
            for veg in range(len(veg_list)):
                if veg_name==veg_list[veg]:
                    print("Vegetable name: {:s}, Price: {:d}, Max Discount: {:.2f}".format(veg_list[veg],veg_list[veg+1],veg_list[veg+2]))
            break
        else:
            print("{} does not have the entered veg.".format(veg_list))
            print("Please enter the exact veg name from the list: ")
            veg_name=input()
            continue

differentelements()