Sublime plugin for anonymising bank statement data

Anonymiser.py

import sublime, sublime_plugin, random, string, re


class AnonymiseCommand(sublime_plugin.TextCommand):
  def replacement(self, s):
    # Figure out which chars to use
    chars = []
    if re.search("[a-z]", s):
      chars += string.ascii_lowercase
    if re.search("[A-Z]", s):
      chars += string.ascii_uppercase
    if re.search("\s", s):
        chars.append(' ')
    if re.search("\d", s):
      chars += string.digits
    # Generate random text with same length
    return ''.join([random.choice(chars) for n in range(len(s))])

  def replacement2(self, s):
    s2 = ''
    for char in s:
      if re.match("[a-z]", char):
        s2 += random.choice(string.ascii_lowercase)
      elif re.match("[A-Z]", char):
        s2 += random.choice(string.ascii_uppercase)
      elif re.match("\d", char):
        s2 += random.choice(string.digits)
      else:
        s2 += char

    return s2

  def run(self, edit):
    view = self.view
    replacements = {}
    # Get all the current selections
    for region in view.sel():
      if not region.empty():
        # Get the selected text
        s = view.substr(region)

        # Check if we have replaced this text on a previous selection
        if s in replacements:
          # Use previous replacement text
          s2 = replacements[s]
        else:
          # Generate new replacement text
          s2 = self.replacement2(s)
          replacements[s] = s2

        # Replace the current selection
        view.replace(edit, region, s2)