'Move the turtle forward by the specified distance.
Aliases: forward | fd
Argument:
distance -- a number (integer or float)
Move the turtle forward by the specified distance, in the direction
the turtle is headed.
Example (for a Turtle instance named turtle):
>>> turtle.position()
(0.00, 0.00)
>>> turtle.forward(25)
>>> turtle.position()
(25.00,0.00)
>>> turtle.forward(-75)
>>> turtle.position()
(-50.00,0.00)'

def forward(self, distance):

    self._go(distance)
