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diff --git a/external/construct/lib/binary.py b/external/construct/lib/binary.py
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+import six
+from construct.lib.py3compat import int2byte
+
+
+if six.PY3:
+    def int_to_bin(number, width = 32):
+        r"""
+        Convert an integer into its binary representation in a bytes object.
+        Width is the amount of bits to generate. If width is larger than the actual
+        amount of bits required to represent number in binary, sign-extension is
+        used. If it's smaller, the representation is trimmed to width bits.
+        Each "bit" is either '\x00' or '\x01'. The MSBit is first.
+    
+        Examples:
+    
+            >>> int_to_bin(19, 5)
+            b'\x01\x00\x00\x01\x01'
+            >>> int_to_bin(19, 8)
+            b'\x00\x00\x00\x01\x00\x00\x01\x01'
+        """
+        number = int(number)
+        if number < 0:
+            number += 1 << width
+        i = width - 1
+        bits = bytearray(width)
+        while number and i >= 0:
+            bits[i] = number & 1
+            number >>= 1
+            i -= 1
+        return bytes(bits)
+
+    # heavily optimized for performance
+    def bin_to_int(bits, signed = False):
+        r"""
+        Logical opposite of int_to_bin. Both '0' and '\x00' are considered zero,
+        and both '1' and '\x01' are considered one. Set sign to True to interpret
+        the number as a 2-s complement signed integer.
+        """
+        bits = "".join("01"[b & 1] for b in bits)
+        if signed and bits[0] == "1":
+            bits = bits[1:]
+            bias = 1 << len(bits)
+        else:
+            bias = 0
+        return int(bits, 2) - bias
+
+    _char_to_bin = [0] * 256
+    _bin_to_char = {}
+    for i in range(256):
+        ch = int2byte(i)
+        bin = int_to_bin(i, 8)
+        # Populate with for both keys i and ch, to support Python 2 & 3
+        _char_to_bin[i] = bin
+        _bin_to_char[bin] = ord(ch)
+
+    def encode_bin(data):
+        """ 
+        Create a binary representation of the given b'' object. Assume 8-bit
+        ASCII. Example:
+    
+            >>> encode_bin('ab')
+            b"\x00\x01\x01\x00\x00\x00\x00\x01\x00\x01\x01\x00\x00\x00\x01\x00"
+        """
+        return six.b("").join(_char_to_bin[int(ch)] for ch in data)
+
+    def decode_bin(data):
+        if len(data) & 7:
+            raise ValueError("Data length must be a multiple of 8")
+        i = 0
+        j = 0
+        l = len(data) // 8
+        arr = bytearray(l)
+        while j < l:
+            arr[j] = _bin_to_char[data[i:i+8]]
+            i += 8
+            j += 1
+        return arr
+    
+    def swap_bytes(bits, bytesize=8):
+        r"""
+        Bits is a b'' object containing a binary representation. Assuming each
+        bytesize bits constitute a bytes, perform a endianness byte swap. Example:
+    
+            >>> swap_bytes(b'00011011', 2)
+            b'11100100'
+        """
+        i = 0
+        l = len(bits)
+        output = [six.b("")] * ((l // bytesize) + 1)
+        j = len(output) - 1
+        while i < l:
+            output[j] = bits[i : i + bytesize]
+            i += bytesize
+            j -= 1
+        return six.b("").join(output)
+
+else:
+
+    def int_to_bin(number, width = 32):
+        r"""
+        Convert an integer into its binary representation in a bytes object.
+        Width is the amount of bits to generate. If width is larger than the actual
+        amount of bits required to represent number in binary, sign-extension is
+        used. If it's smaller, the representation is trimmed to width bits.
+        Each "bit" is either '\x00' or '\x01'. The MSBit is first.
+    
+        Examples:
+    
+            >>> int_to_bin(19, 5)
+            '\x01\x00\x00\x01\x01'
+            >>> int_to_bin(19, 8)
+            '\x00\x00\x00\x01\x00\x00\x01\x01'
+        """
+        if number < 0:
+            number += 1 << width
+        i = width - 1
+        bits = ["\x00"] * width
+        while number and i >= 0:
+            bits[i] = "\x00\x01"[number & 1]
+            number >>= 1
+            i -= 1
+        return "".join(bits)
+
+    # heavily optimized for performance
+    def bin_to_int(bits, signed = False):
+        r"""
+        Logical opposite of int_to_bin. Both '0' and '\x00' are considered zero,
+        and both '1' and '\x01' are considered one. Set sign to True to interpret
+        the number as a 2-s complement signed integer.
+        """
+        bits = "".join("01"[ord(b) & 1] for b in bits)
+        if signed and bits[0] == "1":
+            bits = bits[1:]
+            bias = 1 << len(bits)
+        else:
+            bias = 0
+        return int(bits, 2) - bias
+
+    _char_to_bin = [0] * 256
+    _bin_to_char = {}
+    for i in range(256):
+        ch = int2byte(i)
+        bin = int_to_bin(i, 8)
+        # Populate with for both keys i and ch, to support Python 2 & 3
+        _char_to_bin[i] = bin
+        _bin_to_char[bin] = ch
+
+    def encode_bin(data):
+        """ 
+        Create a binary representation of the given b'' object. Assume 8-bit
+        ASCII. Example:
+    
+            >>> encode_bin('ab')
+            b"\x00\x01\x01\x00\x00\x00\x00\x01\x00\x01\x01\x00\x00\x00\x01\x00"
+        """
+        return "".join(_char_to_bin[ord(ch)] for ch in data)
+
+    def decode_bin(data):
+        if len(data) & 7:
+            raise ValueError("Data length must be a multiple of 8")
+        i = 0
+        j = 0
+        l = len(data) // 8
+        chars = [""] * l
+        while j < l:
+            chars[j] = _bin_to_char[data[i:i+8]]
+            i += 8
+            j += 1
+        return "".join(chars)
+
+    def swap_bytes(bits, bytesize=8):
+        r"""
+        Bits is a b'' object containing a binary representation. Assuming each
+        bytesize bits constitute a bytes, perform a endianness byte swap. Example:
+    
+            >>> swap_bytes(b'00011011', 2)
+            b'11100100'
+        """
+        i = 0
+        l = len(bits)
+        output = [""] * ((l // bytesize) + 1)
+        j = len(output) - 1
+        while i < l:
+            output[j] = bits[i : i + bytesize]
+            i += bytesize
+            j -= 1
+        return "".join(output)