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+print(int('b',16), int('62ba1cd8a',16)) # Prints the hexadecimal representation of the value.
+'''
+testnet : A small replica of bitcoin for developers to test their app without real money.
+We use bitcoin-cli command to communicate with a node. It is a command line utility.
+In this course we use >testnet rather than >bitcoin-cli.
+/
+>testnet help
+>mainnet help
+Prints all the commands to use in testnet or mainnet
+/
+>testnet help getblockchaininfo
+Gets the help for the related command
+/
+>testnet getblockchaininfo
+Makes the query with the method for the testnet. mainnet for the actual chain
+/
+>mainnet getmininginfo
+Gives the mining info
+/
+Check how the nodes talk with each other from https://bitcoin.org/en/developer-reference#protocol-versions
+This changes from version to version. ipv4 / ipv6 / onion
+/
+>testnet getwalletinfo
+Gives the wallet info
+/
+>testnet listtransactions
+The transactions related to wallet
+/
+Code to connect to node
+If you don't have bitcoinrpc install it with pip:
+pip install python-bitcoinrpc
+/
+Code:
+from bitcoinrpc.authproxy import AuthServiceProxy
+
+N = 115792089237316195423570985008687907852837564279074904382605163141518161494337
+big_number = 105936749493397165751943248390023977685888340619776708311600296471039819517671
+
+class RPC:
+
+    def __init__(self, uri):
+        self.rpc = AuthServiceProxy(uri)
+
+    def __getattr__(self, name):
+        """Hack to establish a new AuthServiceProxy every time this is called"""
+        return getattr(self.rpc, name)
+
+rpc_template = "http://%s:%s@%s:%s"
+mainnet = RPC(rpc_template %
+        ('bitcoin', 'python', '68.183.110.103', 8332))
+testnet = RPC(rpc_template %
+        ('bitcoin', 'python', 'localhost', 18332))
+/
+pprint : A package to print objects pretty.Especially JSON objects.
+from helpers import testnet
+from pprint import pprint
+
+pprint(testnet.getblockchaininfo())
+
+
+'''
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