python snmp getter with parser for mac address and ip

snmp.py

#! /usr/bin/env python
from pysnmp import hlapi
from pysnmp.smi import builder
from pyasn1.type.univ import OctetString
from pysnmp.proto.rfc1902 import OctetString, IpAddress

def get(target, oids, credentials, port, engine, context):
    udp_target = hlapi.UdpTransportTarget((target, port))
    object_types = construct_object_types(oids)
    handler = hlapi.getCmd(engine, credentials, udp_target, context, *object_types)
    return fetch(handler, 1)[0]

def construct_object_types(list_of_oids):
    object_types = []
    for oid in list_of_oids:
        object_types.append(hlapi.ObjectType(hlapi.ObjectIdentity(oid)))
    return object_types

def cast(value):
    if type(value) == OctetString:
        mibBuilder = builder.MibBuilder()
        MacAddress, = mibBuilder.importSymbols('SNMPv2-TC', 'MacAddress')
        hex_value = ''.join(['%.2x' % x for x in value.asOctets()])
        macAddress = MacAddress(hexValue=hex_value.zfill(12))
        return macAddress.prettyPrint()
    if type(value) == IpAddress:
        ip = '.'.join(['%d' % x for x in value.asNumbers()])
        return ip

    try:
        return int(value)
    except (ValueError, TypeError):
        try:
            return float(value)
        except (ValueError, TypeError):
            try:
                return str(value)
            except (ValueError, TypeError):
                pass
    return value

def fetch(handler, count):
    result = []
    for i in range(count):
        try:
            error_indication, error_status, error_index, var_binds = next(handler)
            if not error_indication and not error_status:
                items = {}
                for var_bind in var_binds:
                    items[str(var_bind[0])] = cast(var_bind[1])
                result.append(items)
            else:
                raise RuntimeError('Got SNMP error: {0}'.format(error_indication))
        except StopIteration:
            break
    return result

if __name__ == "__main__":
    target = "10.1.44.70"
    oids = [
        '1.3.6.1.2.1.4.22.1.2.6.10.1.45.254',
        '1.3.6.1.2.1.4.22.1.1.6.10.1.45.254',
        '1.3.6.1.2.1.2.2.1.5.6',
        '1.3.6.1.2.1.3.1.1.2.6.1.10.1.45.254',
        '1.3.6.1.2.1.4.20.1.1.10.1.44.70',
    ]
    credentials = hlapi.CommunityData('public')
    port = 161
    engine=hlapi.SnmpEngine()
    context=hlapi.ContextData()
    print(get(target, oids, credentials, port, engine, context))