class_docstr: A GraphItem displays graph information as
  a set of nodes connected by lines (as in 'graph theory', not 'graphics'). 
  Useful for drawing networks, trees, etc.
class_docstr_tok: ["A","GraphItem","displays","graph","information","as","a","set","of","nodes","connected","by","lines","(","as","in","'graph","theory","'",",","not","'graphics","'",")",".","Useful","for","drawing","networks",",","trees",",","etc","."]
docstr: Set the pen used to draw graph lines.
  May be: 
  
    * None to disable line drawing
    * Record array with fields (red, green, blue, alpha, width)
    * Any set of arguments and keyword arguments accepted by
      :func:`mkPen <pyqtgraph.mkPen>`.
    * 'default' to use the default foreground color.
docstr_tok: ["Set","the","pen","used","to","draw","graph","lines",".","May","be",":","*","None","to","disable","line","drawing","*","Record","array","with","fields","(","red",",","green",",","blue",",","alpha",",","width",")","*","Any","set","of","arguments","and","keyword","arguments","accepted","by",":","func",":","`","mkPen","<","pyqtgraph.mkPen",">","`",".","*","'default","'","to","use","the","default","foreground","color","."]
code: def setPen(self, *args, **kwargs):
      """
      Set the pen used to draw graph lines.
      May be:
  
        * None to disable line drawing
        * Record array with fields (red, green, blue, alpha, width)
        * Any set of arguments and keyword arguments accepted by
          :func:`mkPen <pyqtgraph.mkPen>`.
        * 'default' to use the default foreground color.
      """
      if len(args) == 1 and len(kwargs) == 0:
          self.pen = args[0]
      else:
          self.pen = fn.mkPen(*args, **kwargs)
      self.picture = None
      self.update()
  
file_path: pyqtgraph/pyqtgraph/graphicsItems/GraphItem.py
imports: import numpy
  from ..None import functions
  from ..None import getConfigOption
  from ..Qt import QtCore, QtGui
  from .GraphicsObject import GraphicsObject
  from .ScatterPlotItem import ScatterPlotItem
label_desc: Use image node_id 4 for calling the GraphItem obj's underlying member method code with example usage: obj.setPen() without return types