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      "True\n",
      "False\n"
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   "source": [
    "# Write a Python program to check that a string contains only a certain set of characters (in this case a-z, A-Z and 0-9).\n",
    "# Input\n",
    "# \"ABCDEFabcdef123450\"\n",
    "# \"*&%@#!}{\"\n",
    "# Output\n",
    "# True                                                                                                          \n",
    "# False\n",
    "\n",
    "import re\n",
    "def is_allowed_specific_char(string):\n",
    "    charRe = re.compile(r'[^a-zA-Z0-9.]')\n",
    "    string = charRe.search(string)\n",
    "    return not bool(string)\n",
    "\n",
    "print(is_allowed_specific_char(\"ABCDEFabcdef123450\")) \n",
    "print(is_allowed_specific_char(\"*&%@#!}{\"))"
   ]
  }
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