for loop in python ignors some elements

MAX = 10000

def get_dicimal(target_number) :
    i = 1
    while i <= target_number :
        if target_number % i == 0 :
            if i == 1 :
                i = i + 1
            elif i == target_number :
                return True
            else :
                return False
        else :
            i = i + 1


dicimal_list = []
target_list = list(range(2, MAX))

print(target_list)

for i in target_list :
    a = get_dicimal(i)
    print(i, a)
    if a == True :
        dicimal_list.append(i)
        for k in range(1, int(MAX / i)) :
            try :
                target_list.remove(i * k)
            except :
                pass
    else :
        pass

print(target_list)
print(dicimal_list)

result get_dicimal(3) is True but in for loop in line 23, it ignores number 3

so target_list result like this [3, 7, 9, 13, 19, 21, 27, 31, 39, 43, 49, 57, 61, 63, 71...

and dicimal_list = [2, 5, 11, 17, 23, 29, 37, 41, 47, 53, 59, 67, 73, 83, 97, 103, 109...

I guess it was caused by index problem but I don't know why.

It can't be expressed in for loop like i did?

I'm newbie so please teach me.