A path object. The coordinate list can be any sequence object containing
either 2-tuples [(x, y), …] or numeric values [x, y, …].

You can also create a path object from another path object.

In 1.1.6 and later, you can also pass in any object that implements
Python’s buffer API. The buffer should provide read access, and contain C
floats in machine byte order.

The path object implements most parts of the Python sequence interface, and
behaves like a list of (x, y) pairs. You can use len(), item access, and
slicing as usual. However, this does not support slice assignment, or item
and slice deletion.

:param xy: A sequence. The sequence can contain 2-tuples [(x, y), ...]
           or a flat list of numbers [x, y, ...].

Compacts the path, by removing points that are close to each other. This
method modifies the path in place, and returns the number of points left in
the path.

``distance`` is measured as `Manhattan distance`_ and defaults to two
pixels.

Gets the bounding box of the path.

:return: ``(x0, y0, x1, y1)``

Maps the path through a function.

Converts the path to a Python list [(x, y), …].

:param flat: By default, this function returns a list of 2-tuples
             [(x, y), ...].  If this argument is ``True``, it
             returns a flat list [x, y, ...] instead.
:return: A list of coordinates. See ``flat``.

Transforms the path in place, using an affine transform. The matrix is a
6-tuple (a, b, c, d, e, f), and each point is mapped as follows::

    xOut = xIn * a + yIn * b + c
    yOut = xIn * d + yIn * e + f