First try

Packet/PacketPimHello.py

+import struct
+
+
+class PacketPimHello:
+    PIM_TYPE = 0
+    PIM_HDR_OPTS = "! HH"
+    PIM_HDR_OPTS_LEN = struct.calcsize(PIM_HDR_OPTS)
+
+    PIM_MSG_TYPES_LENGTH = {1: 2,
+                            20: 4,
+                            }
+
+    def __init__(self):
+        self.options = {}
+
+    def add_option(self, option_type: int, option_value: int):
+        if option_value is None:
+            del self.options[option_type]
+            return
+        self.options[option_type] = option_value
+
+    def get_options(self):
+        return self.options
+
+    def bytes(self) -> bytes:
+        res = b''
+        for (option_type, option_value) in self.options.items():
+            option_length = self.PIM_MSG_TYPES_LENGTH[option_type]
+            type_length_hdr = struct.pack(self.PIM_HDR_OPTS, option_type, option_length)
+            res += type_length_hdr + struct.pack("! " + str(option_length) + "s", option_value.to_bytes(option_length, byteorder='big'))
+        return res

Packet/PacketPimJoinPrune.py

+import struct
+
+
+class PacketPimJoinPrune:
+    PIM_HDR_JOIN_PRUNE = "! 4S BBH "
+    PIM_HDR_JOIN_PRUNE_LEN = struct.calcsize(PIM_HDR_JOIN_PRUNE)
+
+    def __init__(self, upstream_neighbor_address, hold_time):
+        self.groups = []
+        self.upstream_neighbor_address = upstream_neighbor_address
+        self.hold_time = hold_time
+
+    def add_multicast_group(self, group):
+        # TODO verificar se grupo ja esta na msg
+        self.groups.append(group)
+
+    def bytes(self) -> bytes:
+        msg = struct.pack(self.PIM_HDR_JOIN_PRUNE, self.upstream_neighbor_address, 0, len(self.groups), self.hold_time)
+
+        for multicast_group in self.groups:
+            msg += multicast_group.bytes()
+
+        return msg

Packet/PacketPimJoinPruneMulticastGroup.py

+import struct
+
+
+class PacketPimJoinPruneMulticastGroup:
+    PIM_HDR_JOIN_PRUNE_MULTICAST_GROUP = "! 4s HH"
+    PIM_HDR_JOIN_PRUNE_MULTICAST_GROUP_LEN = struct.calcsize(PIM_HDR_JOIN_PRUNE_MULTICAST_GROUP)
+
+    PIM_HDR_JOINED_PRUNED_SOURCE = "! 4s"
+    PIM_HDR_JOINED_PRUNED_SOURCE_LEN = struct.calcsize(PIM_HDR_JOINED_PRUNED_SOURCE)
+
+
+    def __init__(self, multicast_group, joined_src_addresses, pruned_src_addresses):
+        self.multicast_group = multicast_group
+        self.joined_src_addresses = joined_src_addresses
+        self.pruned_src_addresses = pruned_src_addresses
+
+    def bytes(self) -> bytes:
+        # TODO: verificar multicast_group
+        msg = struct.pack(self.PIM_HDR_JOIN_PRUNE_MULTICAST_GROUP, self.multicast_group, len(self.joined_src_addresses), len(self.pruned_src_addresses))
+
+        for joined_src_address in self.joined_src_addresses:
+            msg = struct.pack(self.PIM_HDR_JOINED_PRUNED_SOURCE, joined_src_address)
+
+        for pruned_src_address in self.pruned_src_addresses:
+            msg = struct.pack(self.PIM_HDR_JOINED_PRUNED_SOURCE, pruned_src_address)
+        # TODO: verificar pruned e joined addrss
+        return msg