Determine the initial difficulty for a bitcoind in regtest mode - once using the RPC call getinfo and once from the genesis block

InitialDifficultyRegTest.ipynb

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    "#\n",
    "# The bits hardcoded in the genesis block - see the call to CreateGenesisBlock in chainparams.cpp\n",
    "#\n",
    "nBits = int('0x207fffff', 16)"
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    "nBits"
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   "source": [
    "difficulty = 256**(29 - (nBits >> 24))*(65535.0 / ((float)(nBits & 0xFFFFFF)))\n",
    "difficulty"
   ]
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   "source": [
    "#\n",
    "# Now do an RPC call to the local regtest server and see what we get. This assumes that you have a\n",
    "# bitcoind listening on port 18332 in regtest mode\n",
    "#\n",
    "import requests\n",
    "headers = {'content-type': 'application/json'}\n",
    "url = \"http://localhost:18332\"\n",
    "payload = {\"method\": \"getinfo\", \"params\": [], \"jsonrpc\": \"2.0\", \"id\": 1}        \n",
    "r = requests.post(url, json=payload, headers=headers, auth=(\"user\", \"password\"))\n",
    "json = r.json()['result']\n",
    "print(json['difficulty'])"
   ]
  }
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