Pythonic Circular List

Question

Say I have a list,

l = [1, 2, 3, 4, 5, 6, 7, 8]

I want to grab the index of an arbitrary element and the values of its neighbors. For examp

Answer 1

Using the modulo method that others have mentioned I have created a class with a property that implements a circular list.

class Circle:
    """Creates a circular array of numbers

    >>> c = Circle(30)
    >>> c.position
    -1
    >>> c.position = 10
    >>> c.position
    10
    >>> c.position = 20
    >>> c.position
    20
    >>> c.position = 30
    >>> c.position
    0
    >>> c.position = -5
    >>> c.position
    25
    >>>

    """
    def __init__(self, size):
        if not isinstance(size, int):  # validating length
            raise TypeError("Only integers are allowed")
        self.size = size

    @property
    def position(self):
        try:
            return self._position
        except AttributeError:
            return -1

    @position.setter
    def position(self, value):
        positions = [x for x in range(0, self.size)]
        i = len(positions) - 1
        k = positions[(i + value + 1) % len(positions)]
        self._position = k