code: def _calculate_tk(source):
      """Reverse engineered cross-site request protection."""
      # Source: https://github.com/soimort/translate-shell/issues/94#issuecomment-165433715
      # Source: http://www.liuxiatool.com/t.php
  
      def c_int(x, nbits=32):
          """C cast to int32, int16, int8..."""
          return (x & ((1 << (nbits - 1)) - 1)) - (
              x & (1 << (nbits - 1))
          )
  
      def c_uint(x, nbits=32):
          """C cast to uint32, uint16, uint8..."""
          return x & ((1 << nbits) - 1)
  
      tkk = [406398, 561666268 + 1526272306]
      b = tkk[0]
  
      if PY2:
          d = map(ord, source)
      else:
          d = source.encode("utf-8")
  
      def RL(a, b):
          for c in range(0, len(b) - 2, 3):
              d = b[c + 2]
              d = ord(d) - 87 if d >= "a" else int(d)
              xa = c_uint(a)
              d = xa >> d if b[c + 1] == "+" else xa << d
              a = a + d & 4294967295 if b[c] == "+" else a ^ d
          return c_int(a)
  
      a = b
  
      for di in d:
          a = RL(a + di, "+-a^+6")
  
      a = RL(a, "+-3^+b+-f")
      a ^= tkk[1]
      a = a if a >= 0 else ((a & 2147483647) + 2147483648)
      a %= pow(10, 6)
  
      tk = "{0:d}.{1:d}".format(a, a ^ b)
      return tk
  
file_path: TextBlob/textblob/translate.py
imports: from __future__ import absolute_import
  import codecs
  import json
  import re
  from textblob.compat import PY2, request, urlencode
  from textblob.exceptions import TranslatorError, NotTranslated
label_desc: Use image node_id 2 for calling a global function with example usage: _calculate_tk(source) and returns: tk, unknown, unknown, c_int