'Return the angle of the line from the turtle\'s position to (x, y).
Arguments:
x -- a number   or  a pair/vector of numbers   or   a turtle instance
y -- a number       None                            None
call: distance(x, y)         # two coordinates
--or: distance((x, y))       # a pair (tuple) of coordinates
--or: distance(vec)          # e.g. as returned by pos()
--or: distance(mypen)        # where mypen is another turtle
Return the angle, between the line from turtle-position to position
specified by x, y and the turtle\'s start orientation. (Depends on
modes - "standard" or "logo")
Example (for a Turtle instance named turtle):
>>> turtle.pos()
(10.00, 10.00)
>>> turtle.towards(0,0)
225.0'

def towards(self, x, y=None):

    if (y is not None):
        pos = Vec2D(x, y)
    if isinstance(x, Vec2D):
        pos = x
    elif isinstance(x, tuple):
        pos = Vec2D(*x)
    elif isinstance(x, TNavigator):
        pos = x._position
    (x, y) = (pos - self._position)
    result = (round(((math.atan2(y, x) * 180.0) / math.pi), 10) % 360.0)
    result /= self._degreesPerAU
    return ((self._angleOffset + (self._angleOrient * result)) % self._fullcircle)
