code: def _prop_descriptions(self):
      return """\
          arrangement
              If value is `snap` (the default), the node arrangement
              is assisted by automatic snapping of elements to
              preserve space between nodes specified via `nodepad`.
              If value is `perpendicular`, the nodes can only move
              along a line perpendicular to the flow. If value is
              `freeform`, the nodes can freely move on the plane. If
              value is `fixed`, the nodes are stationary.
          customdata
              Assigns extra data each datum. This may be useful when
              listening to hover, click and selection events. Note
              that, "scatter" traces also appends customdata items in
              the markers DOM elements
          customdatasrc
              Sets the source reference on Chart Studio Cloud for
              `customdata`.
          domain
              :class:`plotly.graph_objects.sankey.Domain` instance or
              dict with compatible properties
          hoverinfo
              Determines which trace information appear on hover. If
              `none` or `skip` are set, no information is displayed
              upon hovering. But, if `none` is set, click and hover
              events are still fired. Note that this attribute is
              superseded by `node.hoverinfo` and `node.hoverinfo` for
              nodes and links respectively.
          hoverlabel
              :class:`plotly.graph_objects.sankey.Hoverlabel`
              instance or dict with compatible properties
          ids
              Assigns id labels to each datum. These ids for object
              constancy of data points during animation. Should be an
              array of strings, not numbers or any other type.
          idssrc
              Sets the source reference on Chart Studio Cloud for
              `ids`.
          legend
              Sets the reference to a legend to show this trace in.
              References to these legends are "legend", "legend2",
              "legend3", etc. Settings for these legends are set in
              the layout, under `layout.legend`, `layout.legend2`,
              etc.
          legendgrouptitle
              :class:`plotly.graph_objects.sankey.Legendgrouptitle`
              instance or dict with compatible properties
          legendrank
              Sets the legend rank for this trace. Items and groups
              with smaller ranks are presented on top/left side while
              with "reversed" `legend.traceorder` they are on
              bottom/right side. The default legendrank is 1000, so
              that you can use ranks less than 1000 to place certain
              items before all unranked items, and ranks greater than
              1000 to go after all unranked items. When having
              unranked or equal rank items shapes would be displayed
              after traces i.e. according to their order in data and
              layout.
          legendwidth
              Sets the width (in px or fraction) of the legend for
              this trace.
          link
              The links of the Sankey plot.
          meta
              Assigns extra meta information associated with this
              trace that can be used in various text attributes.
              Attributes such as trace `name`, graph, axis and
              colorbar `title.text`, annotation `text`
              `rangeselector`, `updatemenues` and `sliders` `label`
              text all support `meta`. To access the trace `meta`
              values in an attribute in the same trace, simply use
              `%{meta[i]}` where `i` is the index or key of the
              `meta` item in question. To access trace `meta` in
              layout attributes, use `%{data[n[.meta[i]}` where `i`
              is the index or key of the `meta` and `n` is the trace
              index.
          metasrc
              Sets the source reference on Chart Studio Cloud for
              `meta`.
          name
              Sets the trace name. The trace name appears as the
              legend item and on hover.
          node
              The nodes of the Sankey plot.
          orientation
              Sets the orientation of the Sankey diagram.
          selectedpoints
              Array containing integer indices of selected points.
              Has an effect only for traces that support selections.
              Note that an empty array means an empty selection where
              the `unselected` are turned on for all points, whereas,
              any other non-array values means no selection all where
              the `selected` and `unselected` styles have no effect.
          stream
              :class:`plotly.graph_objects.sankey.Stream` instance or
              dict with compatible properties
          textfont
              Sets the font for node labels
          uid
              Assign an id to this trace, Use this to provide object
              constancy between traces during animations and
              transitions.
          uirevision
              Controls persistence of some user-driven changes to the
              trace: `constraintrange` in `parcoords` traces, as well
              as some `editable: true` modifications such as `name`
              and `colorbar.title`. Defaults to `layout.uirevision`.
              Note that other user-driven trace attribute changes are
              controlled by `layout` attributes: `trace.visible` is
              controlled by `layout.legend.uirevision`,
              `selectedpoints` is controlled by
              `layout.selectionrevision`, and `colorbar.(x|y)`
              (accessible with `config: {editable: true}`) is
              controlled by `layout.editrevision`. Trace changes are
              tracked by `uid`, which only falls back on trace index
              if no `uid` is provided. So if your app can add/remove
              traces before the end of the `data` array, such that
              the same trace has a different index, you can still
              preserve user-driven changes if you give each trace a
              `uid` that stays with it as it moves.
          valueformat
              Sets the value formatting rule using d3 formatting
              mini-languages which are very similar to those in
              Python. For numbers, see:
              https://github.com/d3/d3-format/tree/v1.4.5#d3-format.
          valuesuffix
              Adds a unit to follow the value in the hover tooltip.
              Add a space if a separation is necessary from the
              value.
          visible
              Determines whether or not this trace is visible. If
              "legendonly", the trace is not drawn, but can appear as
              a legend item (provided that the legend itself is
              visible).
          """
  
imports: from plotly.basedatatypes import BaseTraceType
  import copy
label_desc: Use image node_id 54 for calling the Sankey obj's underlying member method code with example usage: obj._prop_descriptions() and returns: str