code: def build_freeform(self, start_x=0, start_y=0, scale=1.0):
          
          try:
              x_scale, y_scale = scale
          except TypeError:
              x_scale = y_scale = scale
  
          return FreeformBuilder.new(self, start_x, start_y, x_scale, y_scale)
docs: Return |FreeformBuilder| object to specify a freeform shape.
  
          The optional *start_x* and *start_y* arguments specify the starting
          pen position in local coordinates. They will be rounded to the
          nearest integer before use and each default to zero.
  
          The optional *scale* argument specifies the size of local coordinates
          proportional to slide coordinates (EMU). If the vertical scale is
          different than the horizontal scale (local coordinate units are
          "rectangular"), a pair of numeric values can be provided as the
          *scale* argument, e.g. `scale=(1.0, 2.0)`. In this case the first
          number is interpreted as the horizontal (X) scale and the second as
          the vertical (Y) scale.
  
          A convenient method for calculating scale is to divide a |Length|
          object by an equivalent count of local coordinate units, e.g.
          `scale = Inches(1)/1000` for 1000 local units per inch.