class_docstr: Chart public functions
class_docstr_tok: ["Chart","public","functions"]
docstr: Add an xml filter for in tree post processing
docstr_tok: ["Add","an","xml","filter","for","in","tree","post","processing"]
code: def add_xml_filter(self, callback):
      """Add an xml filter for in tree post processing"""
      self.xml_filters.append(callback)
      return self
  
imports: import base64
  import io
  from pygal._compat import is_list_like
  from pygal.graph.base import BaseGraph
label_desc: Use image node_id 3 for calling the PublicApi obj's underlying member method code with example usage: obj.add_xml_filter(callback) and returns: self