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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def draw_line2d(data, obj):
 """Returns the PGFPlots code for an Line2D environment. """

    content = []
    addplot_options = []

    # If line is of length 0, do nothing.  Otherwise, an empty \addplot table will be
    # created, which will be interpreted as an external data source in either the file
    # '' or '.tex'.  Instead, render nothing.
    if len(obj.get_xdata()) == 0:
        return data, []

    # get the linewidth (in pt)
    line_width = mypath.mpl_linewidth2pgfp_linewidth(data, obj.get_linewidth())
    if line_width:
        addplot_options.append(line_width)

    # get line color
    color = obj.get_color()
    data, line_xcolor, _ = mycol.mpl_color2xcolor(data, color)
    addplot_options.append(line_xcolor)

    alpha = obj.get_alpha()
    if alpha is not None:
        addplot_options.append("opacity={}".format(alpha))

    linestyle = mypath.mpl_linestyle2pgfplots_linestyle(obj.get_linestyle(), line=obj)
    if linestyle is not None and linestyle != "solid":
        addplot_options.append(linestyle)

    marker_face_color = obj.get_markerfacecolor()
    marker_edge_color = obj.get_markeredgecolor()
    data, marker, extra_mark_options = _mpl_marker2pgfp_marker(
        data, obj.get_marker(), marker_face_color
    )
    if marker:
        _marker(
            obj,
            data,
            marker,
            addplot_options,
            extra_mark_options,
            marker_face_color,
            marker_edge_color,
            line_xcolor,
        )

    if marker and linestyle is None:
        addplot_options.append("only marks")

    # Check if a line is in a legend and forget it if not.
    # Fixes <https://github.com/nschloe/matplotlib2tikz/issues/167>.
    legend_text = get_legend_text(obj)
    if legend_text is None and has_legend(obj.axes):
        addplot_options.append("forget plot")

    # process options
    content.append("\\addplot ")
    if addplot_options:
        content.append("[{}]\n".format(", ".join(addplot_options)))

    c, axis_options = _table(obj, data)
    content += c

    if legend_text is not None:
        content.append("\\addlegendentry{{{}}}\n".format(legend_text))

    return data, content