diff --git a/pyvis/JScode.py b/pyvis/JScode.py
new file mode 100644
index 0000000..76224ba
--- /dev/null
+++ b/pyvis/JScode.py
@@ -0,0 +1,464 @@
+"""Implementation of JSONEncoder with a JS type for direct injection into JS objects
+"""
+import re
+
+try:
+    from _json import encode_basestring_ascii as c_encode_basestring_ascii
+except ImportError:
+    c_encode_basestring_ascii = None
+try:
+    from _json import encode_basestring as c_encode_basestring
+except ImportError:
+    c_encode_basestring = None
+try:
+    from _json import make_encoder as c_make_encoder
+except ImportError:
+    c_make_encoder = None
+
+ESCAPE = re.compile(r'[\x00-\x1f\\"\b\f\n\r\t]')
+ESCAPE_ASCII = re.compile(r'([\\"]|[^\ -~])')
+HAS_UTF8 = re.compile(b'[\x80-\xff]')
+ESCAPE_DCT = {
+    '\\': '\\\\',
+    '"': '\\"',
+    '\b': '\\b',
+    '\f': '\\f',
+    '\n': '\\n',
+    '\r': '\\r',
+    '\t': '\\t',
+}
+for i in range(0x20):
+    ESCAPE_DCT.setdefault(chr(i), '\\u{0:04x}'.format(i))
+    #ESCAPE_DCT.setdefault(chr(i), '\\u%04x' % (i,))
+del i
+
+INFINITY = float('inf')
+
+def py_encode_basestring(s):
+    """Return a JSON representation of a Python string
+
+    """
+    def replace(match):
+        return ESCAPE_DCT[match.group(0)]
+    return '"' + ESCAPE.sub(replace, s) + '"'
+
+
+encode_basestring = (c_encode_basestring or py_encode_basestring)
+
+
+def py_encode_basestring_ascii(s):
+    """Return an ASCII-only JSON representation of a Python string
+
+    """
+    def replace(match):
+        s = match.group(0)
+        try:
+            return ESCAPE_DCT[s]
+        except KeyError:
+            n = ord(s)
+            if n < 0x10000:
+                return '\\u{0:04x}'.format(n)
+                #return '\\u%04x' % (n,)
+            else:
+                # surrogate pair
+                n -= 0x10000
+                s1 = 0xd800 | ((n >> 10) & 0x3ff)
+                s2 = 0xdc00 | (n & 0x3ff)
+                return '\\u{0:04x}\\u{1:04x}'.format(s1, s2)
+    return '"' + ESCAPE_ASCII.sub(replace, s) + '"'
+
+
+encode_basestring_ascii = (
+    c_encode_basestring_ascii or py_encode_basestring_ascii)
+
+class JS():
+    """Class to be serialised as is (for example, to add functions into JS objects"""
+    source = ""
+    def __init__(self, source):
+        if type(source) is str:
+            self.source = source
+        else:
+            raise TypeError('JS object requires str as the source')
+
+class JSONEncoder(object):
+    """Extensible JSON <https://json.org> encoder for Python data structures.
+
+    Supports the following objects and types by default:
+
+    +-------------------+---------------+
+    | Python            | JSON / JS     |
+    +===================+===============+
+    | dict              | object        |
+    +-------------------+---------------+
+    | list, tuple       | array         |
+    +-------------------+---------------+
+    | str               | string        |
+    +-------------------+---------------+
+    | int, float        | number        |
+    +-------------------+---------------+
+    | True              | true          |
+    +-------------------+---------------+
+    | False             | false         |
+    +-------------------+---------------+
+    | None              | null          |
+    +-------------------+---------------+
+    | JScode.JS         | javascript    |
+    +-------------------+---------------+
+
+    To extend this to recognize other objects, subclass and implement a
+    ``.default()`` method with another method that returns a serializable
+    object for ``o`` if possible, otherwise it should call the superclass
+    implementation (to raise ``TypeError``).
+
+    """
+    item_separator = ', '
+    key_separator = ': '
+    def __init__(self, *, skipkeys=False, ensure_ascii=True,
+            check_circular=True, allow_nan=True, sort_keys=False,
+            indent=None, separators=None, default=None):
+        """Constructor for JSONEncoder, with sensible defaults.
+
+        If skipkeys is false, then it is a TypeError to attempt
+        encoding of keys that are not str, int, float or None.  If
+        skipkeys is True, such items are simply skipped.
+
+        If ensure_ascii is true, the output is guaranteed to be str
+        objects with all incoming non-ASCII characters escaped.  If
+        ensure_ascii is false, the output can contain non-ASCII characters.
+
+        If check_circular is true, then lists, dicts, and custom encoded
+        objects will be checked for circular references during encoding to
+        prevent an infinite recursion (which would cause an RecursionError).
+        Otherwise, no such check takes place.
+
+        If allow_nan is true, then NaN, Infinity, and -Infinity will be
+        encoded as such.  This behavior is not JSON specification compliant,
+        but is consistent with most JavaScript based encoders and decoders.
+        Otherwise, it will be a ValueError to encode such floats.
+
+        If sort_keys is true, then the output of dictionaries will be
+        sorted by key; this is useful for regression tests to ensure
+        that JSON serializations can be compared on a day-to-day basis.
+
+        If indent is a non-negative integer, then JSON array
+        elements and object members will be pretty-printed with that
+        indent level.  An indent level of 0 will only insert newlines.
+        None is the most compact representation.
+
+        If specified, separators should be an (item_separator, key_separator)
+        tuple.  The default is (', ', ': ') if *indent* is ``None`` and
+        (',', ': ') otherwise.  To get the most compact JSON representation,
+        you should specify (',', ':') to eliminate whitespace.
+
+        If specified, default is a function that gets called for objects
+        that can't otherwise be serialized.  It should return a JSON encodable
+        version of the object or raise a ``TypeError``.
+
+        """
+
+        self.skipkeys = skipkeys
+        self.ensure_ascii = ensure_ascii
+        self.check_circular = check_circular
+        self.allow_nan = allow_nan
+        self.sort_keys = sort_keys
+        self.indent = indent
+        if separators is not None:
+            self.item_separator, self.key_separator = separators
+        elif indent is not None:
+            self.item_separator = ','
+        if default is not None:
+            self.default = default
+
+    def default(self, o):
+        """Implement this method in a subclass such that it returns
+        a serializable object for ``o``, or calls the base implementation
+        (to raise a ``TypeError``).
+
+        For example, to support arbitrary iterators, you could
+        implement default like this::
+
+            def default(self, o):
+                try:
+                    iterable = iter(o)
+                except TypeError:
+                    pass
+                else:
+                    return list(iterable)
+                # Let the base class default method raise the TypeError
+                return JSONEncoder.default(self, o)
+
+        """
+        raise TypeError(f'Object of type {o.__class__.__name__} '
+                        f'is not JSON serializable')
+
+    def encode(self, o):
+        """Return a JSON string representation of a Python data structure.
+
+        >>> from json.encoder import JSONEncoder
+        >>> JSONEncoder().encode({"foo": ["bar", "baz"]})
+        '{"foo": ["bar", "baz"]}'
+
+        """
+        # This is for extremely simple cases and benchmarks.
+        if isinstance(o, str):
+            if self.ensure_ascii:
+                return encode_basestring_ascii(o)
+            else:
+                return encode_basestring(o)
+        elif isinstance(o, JS):
+            return o.source
+        # This doesn't pass the iterator directly to ''.join() because the
+        # exceptions aren't as detailed.  The list call should be roughly
+        # equivalent to the PySequence_Fast that ''.join() would do.
+        chunks = self.iterencode(o, _one_shot=True)
+        if not isinstance(chunks, (list, tuple)):
+            chunks = list(chunks)
+        return ''.join(chunks)
+
+    def iterencode(self, o, _one_shot=False):
+        """Encode the given object and yield each string
+        representation as available.
+
+        For example::
+
+            for chunk in JSONEncoder().iterencode(bigobject):
+                mysocket.write(chunk)
+
+        """
+        if self.check_circular:
+            markers = {}
+        else:
+            markers = None
+        if self.ensure_ascii:
+            _encoder = encode_basestring_ascii
+        else:
+            _encoder = encode_basestring
+
+        def floatstr(o, allow_nan=self.allow_nan,
+                _repr=float.__repr__, _inf=INFINITY, _neginf=-INFINITY):
+            # Check for specials.  Note that this type of test is processor
+            # and/or platform-specific, so do tests which don't depend on the
+            # internals.
+
+            if o != o:
+                text = 'NaN'
+            elif o == _inf:
+                text = 'Infinity'
+            elif o == _neginf:
+                text = '-Infinity'
+            else:
+                return _repr(o)
+
+            if not allow_nan:
+                raise ValueError(
+                    "Out of range float values are not JSON compliant: " +
+                    repr(o))
+
+            return text
+
+
+        if False:  # (_one_shot and c_make_encoder is not None and self.indent is None):
+            _iterencode = c_make_encoder(
+                markers, self.default, _encoder, self.indent,
+                self.key_separator, self.item_separator, self.sort_keys,
+                self.skipkeys, self.allow_nan)
+        else:
+            _iterencode = _make_iterencode(
+                markers, self.default, _encoder, self.indent, floatstr,
+                self.key_separator, self.item_separator, self.sort_keys,
+                self.skipkeys, _one_shot)
+        if isinstance(o, JS):
+            return o.source
+        return _iterencode(o, 0)
+
+def _make_iterencode(markers, _default, _encoder, _indent, _floatstr,
+        _key_separator, _item_separator, _sort_keys, _skipkeys, _one_shot,
+        ## HACK: hand-optimized bytecode; turn globals into locals
+        ValueError=ValueError,
+        dict=dict,
+        float=float,
+        id=id,
+        int=int,
+        isinstance=isinstance,
+        list=list,
+        str=str,
+        tuple=tuple,
+        JS=JS,
+        _intstr=int.__repr__,
+    ):
+
+    if _indent is not None and not isinstance(_indent, str):
+        _indent = ' ' * _indent
+
+    def _iterencode_list(lst, _current_indent_level):
+        if not lst:
+            yield '[]'
+            return
+        if markers is not None:
+            markerid = id(lst)
+            if markerid in markers:
+                raise ValueError("Circular reference detected")
+            markers[markerid] = lst
+        buf = '['
+        if _indent is not None:
+            _current_indent_level += 1
+            newline_indent = '\n' + _indent * _current_indent_level
+            separator = _item_separator + newline_indent
+            buf += newline_indent
+        else:
+            newline_indent = None
+            separator = _item_separator
+        first = True
+        for value in lst:
+            if first:
+                first = False
+            else:
+                buf = separator
+            if isinstance(value, str):
+                yield buf + _encoder(value)
+            elif isinstance(value, JS):
+                yield buf + value.source
+            elif value is None:
+                yield buf + 'null'
+            elif value is True:
+                yield buf + 'true'
+            elif value is False:
+                yield buf + 'false'
+            elif isinstance(value, int):
+                # Subclasses of int/float may override __repr__, but we still
+                # want to encode them as integers/floats in JSON. One example
+                # within the standard library is IntEnum.
+                yield buf + _intstr(value)
+            elif isinstance(value, float):
+                # see comment above for int
+                yield buf + _floatstr(value)
+            else:
+                yield buf
+                if isinstance(value, (list, tuple)):
+                    chunks = _iterencode_list(value, _current_indent_level)
+                elif isinstance(value, dict):
+                    chunks = _iterencode_dict(value, _current_indent_level)
+                else:
+                    chunks = _iterencode(value, _current_indent_level)
+                yield from chunks
+        if newline_indent is not None:
+            _current_indent_level -= 1
+            yield '\n' + _indent * _current_indent_level
+        yield ']'
+        if markers is not None:
+            del markers[markerid]
+
+    def _iterencode_dict(dct, _current_indent_level):
+        if not dct:
+            yield '{}'
+            return
+        if markers is not None:
+            markerid = id(dct)
+            if markerid in markers:
+                raise ValueError("Circular reference detected")
+            markers[markerid] = dct
+        yield '{'
+        if _indent is not None:
+            _current_indent_level += 1
+            newline_indent = '\n' + _indent * _current_indent_level
+            item_separator = _item_separator + newline_indent
+            yield newline_indent
+        else:
+            newline_indent = None
+            item_separator = _item_separator
+        first = True
+        if _sort_keys:
+            items = sorted(dct.items())
+        else:
+            items = dct.items()
+        for key, value in items:
+            if isinstance(key, str):
+                pass
+            # JavaScript is weakly typed for these, so it makes sense to
+            # also allow them.  Many encoders seem to do something like this.
+            elif isinstance(key, float):
+                # see comment for int/float in _make_iterencode
+                key = _floatstr(key)
+            elif key is True:
+                key = 'true'
+            elif key is False:
+                key = 'false'
+            elif key is None:
+                key = 'null'
+            elif isinstance(key, int):
+                # see comment for int/float in _make_iterencode
+                key = _intstr(key)
+            elif _skipkeys:
+                continue
+            else:
+                raise TypeError(f'keys must be str, int, float, bool or None, '
+                                f'not {key.__class__.__name__}')
+            if first:
+                first = False
+            else:
+                yield item_separator
+            yield _encoder(key)
+            yield _key_separator
+            if isinstance(value, str):
+                yield _encoder(value)
+            elif isinstance(value, JS):
+                yield value.source
+            elif value is None:
+                yield 'null'
+            elif value is True:
+                yield 'true'
+            elif value is False:
+                yield 'false'
+            elif isinstance(value, int):
+                # see comment for int/float in _make_iterencode
+                yield _intstr(value)
+            elif isinstance(value, float):
+                # see comment for int/float in _make_iterencode
+                yield _floatstr(value)
+            else:
+                if isinstance(value, (list, tuple)):
+                    chunks = _iterencode_list(value, _current_indent_level)
+                elif isinstance(value, dict):
+                    chunks = _iterencode_dict(value, _current_indent_level)
+                else:
+                    chunks = _iterencode(value, _current_indent_level)
+                yield from chunks
+        if newline_indent is not None:
+            _current_indent_level -= 1
+            yield '\n' + _indent * _current_indent_level
+        yield '}'
+        if markers is not None:
+            del markers[markerid]
+
+    def _iterencode(o, _current_indent_level):
+        if isinstance(o, str):
+            yield _encoder(o)
+        elif isinstance(o, JS):
+            yield o.source
+        elif o is None:
+            yield 'null'
+        elif o is True:
+            yield 'true'
+        elif o is False:
+            yield 'false'
+        elif isinstance(o, int):
+            # see comment for int/float in _make_iterencode
+            yield _intstr(o)
+        elif isinstance(o, float):
+            # see comment for int/float in _make_iterencode
+            yield _floatstr(o)
+        elif isinstance(o, (list, tuple)):
+            yield from _iterencode_list(o, _current_indent_level)
+        elif isinstance(o, dict):
+            yield from _iterencode_dict(o, _current_indent_level)
+        else:
+            if markers is not None:
+                markerid = id(o)
+                if markerid in markers:
+                    raise ValueError("Circular reference detected")
+                markers[markerid] = o
+            o = _default(o)
+            yield from _iterencode(o, _current_indent_level)
+            if markers is not None:
+                del markers[markerid]
+    return _iterencode
diff --git a/pyvis/network.py b/pyvis/network.py
index 8deb915..87eb078 100644
--- a/pyvis/network.py
+++ b/pyvis/network.py
@@ -14,6 +14,7 @@
 from .node import Node
 from .options import Options, Configure
 from .utils import check_html
+from .JScode import JSONEncoder as JS_encoder
 
 
 class Network(object):
@@ -93,6 +94,10 @@ def __init__(self,
         self.path = "template.html"
         self.template_dir = os.path.dirname(__file__) + "/templates/"
         self.templateEnv = Environment(loader=FileSystemLoader(self.template_dir))
+        if "json.dumps_kwargs" in self.templateEnv.policies:
+            self.templateEnv.policies["json.dumps_kwargs"].update({"cls": JS_encoder})
+        else:
+            self.templateEnv.policies["json.dumps_kwargs"] = {"cls": JS_encoder}
 
         if cdn_resources == "local" and notebook == True:
             print("Warning: When  cdn_resources is 'local' jupyter notebook has issues displaying graphics on chrome/safari."
@@ -590,6 +595,11 @@ def set_template_dir(self, template_directory, template_file='template.html'):
         self.path = template_file
         self.template_dir = template_directory
         self.templateEnv = Environment(loader=FileSystemLoader(self.template_dir))
+        if "json.dumps_kwargs" in self.templateEnv.policies:
+            self.templateEnv.policies["json.dumps_kwargs"].update({"cls": JS_encoder})
+        else:
+            self.templateEnv.policies["json.dumps_kwargs"] = {"cls": JS_encoder}
+
 
     def from_DOT(self, dot):
         """