def get_pins(observed):
    nums = []
    keypad = [['1', '2', '3'], ['4', '5', '6'], ['7', '8', '9'], ['', '0', '']]
    for elem in observed:
        for number_list in keypad:
            if elem in number_list:
                keys = ''
                keys += (''.join([number_list[i] for i in range(len(number_list))
                if i in range(number_list.index(elem)- 1, number_list.index(elem) + 2)]))
                keys +=(''.join([number_list_[number_list.index(elem)] for number_list_ in keypad
                if keypad.index(number_list_) in range(keypad.index(number_list) - 1, keypad.index(number_list) + 2) ]))
                nums.append(keys)
    for i in range (len(nums)):
        for elem in nums[i]:
            if nums[i].count(elem) >= 2:
                nums[i] = nums[i].replace(elem, '', nums.count(elem) - (nums.count(elem)- 1))
    result = []
    if len(nums) == 1:
        return [x for x in nums[0]]
    else:
        for num in nums[0]:
            result_ = []
            result_.append(num)
            for i in range(1, len(nums)):
                result_ = ([num + x for num in result_ for x in nums[i]])
            result.extend(result_)

    return result