code: func (f *Fpdf) TransformSkewX(angleX, x, y float64) {
  	f.TransformSkew(angleX, 0, x, y)
  }
docs: // TransformSkewX horizontally skews the following text, drawings and images
  // keeping the point (x, y) stationary. angleX ranges from -90 degrees (skew to
  // the left) to 90 degrees (skew to the right).
  //
  // The TransformBegin() example demonstrates this method.