docstr: Generate ASCII Summary Table
          
docstr_tok: ["Generate","ASCII","Summary","Table"]
code: def as_text(self):
      """Generate ASCII Summary Table"""
  
      tables = self.tables
      settings = self.settings
      title = self.title
      extra_txt = self.extra_txt
  
      pad_col, pad_index, widest = _measure_tables(tables, settings)
  
      rule_equal = widest * "="
  
      simple_tables = _simple_tables(
          tables, settings, pad_col, pad_index
      )
      tab = [x.as_text() for x in simple_tables]
  
      tab = "\n".join(tab)
      tab = tab.split("\n")
      tab[0] = rule_equal
      tab.append(rule_equal)
      tab = "\n".join(tab)
  
      if title is not None:
          title = title
          if len(title) < widest:
              title = " " * int(widest / 2 - len(title) / 2) + title
      else:
          title = ""
  
      txt = [textwrap.wrap(x, widest) for x in extra_txt]
      txt = ["\n".join(x) for x in txt]
      txt = "\n".join(txt)
  
      out = "\n".join([title, tab, txt])
  
      return out
  
imports: from statsmodels.compat.pandas import FUTURE_STACK
  from statsmodels.compat.python import lzip
  import datetime
  from functools import reduce
  import re
  import textwrap
  import numpy
  import pandas
  from .table import SimpleTable
  from .tableformatting import fmt_latex, fmt_txt
label_desc: Use image node_id 12 for calling the Summary obj's underlying member method code with example usage: obj.as_text() and returns: out