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diff --git a/project2/proj2_s4498062/dns/resolver.py b/project2/proj2_s4498062/dns/resolver.py
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+++ b/project2/proj2_s4498062/dns/resolver.py
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+#!/usr/bin/env python2
+
+""" DNS Resolver
+
+This module contains a class for resolving hostnames. You will have to implement
+things in this module. This resolver will be both used by the DNS client and the
+DNS server, but with a different list of servers.
+"""
+
+import socket
+
+from dns.cache import RecordCache
+from dns.classes import Class
+from dns.message import Message, Header, Question
+from dns.rcodes import RCode
+from dns.types import Type
+
+class Resolver(object):
+    """ DNS resolver """
+    
+    def __init__(self, caching, ttl):
+        """ Initialize the resolver
+        
+        Args:
+            caching (bool): caching is enabled if True
+            ttl (int): ttl of cache entries (if > 0)
+        """
+        self.caching = caching
+        self.ttl = ttl
+
+    def gethostbyname(self, hostname):
+        """ Translate a host name to IPv4 address.
+
+        Currently this method contains an example. You will have to replace
+        this example with example with the algorithm described in section
+        5.3.3 in RFC 1034.
+
+        Args:
+            hostname (str): the hostname to resolve
+
+        Returns:
+            (str, [str], [str]): (hostname, aliaslist, ipaddrlist)
+        """
+        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        sock.settimeout(timeout)
+
+        # Create and send query
+        question = dns.message.Question(hostname, Type.A, Class.IN)
+        header = dns.message.Header(9001, 0, 1, 0, 0, 0)
+        header.qr = 0
+        header.opcode = 0
+        header.rd = 1
+        query = dns.message.Message(header, [question])
+        sock.sendto(query.to_bytes(), ("8.8.8.8", 53))
+
+        # Receive response
+        data = sock.recv(512)
+        response = dns.message.Message.from_bytes(data)
+
+        # Get data
+        aliases = []
+        for additional in response.additionals:
+            if additional.type_ == Type.CNAME:
+                aliases.append(additional.rdata.data)
+        addresses = []
+        for answer in response.answers:
+            if answer.type_ == Type.A:
+                addresses.append(answer.rdata.data)
+
+        return hostname, aliases, addresses