pdf_annotate: syntax error

[jedhelmers]

I'm a python noob so I'm probably doing something simple very wrong, but...
I'm trying to run the example from the documentation, but it says there's a syntax error in graphics.py.
Code:

from pdf_annotate import PdfAnnotator, Location, Appearance
a = PdfAnnotator('a.pdf')
a.add_annotation(
    'square',
    Location(x1=50, y1=50, x2=100, y2=100, page=0),
    Appearance(stroke_color=(1, 0, 0), stroke_width=5),
)
a.write('b.pdf')  # or use overwrite=True if you feel lucky

In terminal:

python sample.py

Output:

Traceback (most recent call last):
  File "sample.py", line 1, in <module>
    from pdf_annotate import PdfAnnotator, Location, Appearance
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/__init__.py", line 2, in <module>
    from pdf_annotate.annotator import PdfAnnotator
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/annotator.py", line 15, in <module>
    from pdf_annotate.annotations.image import Image
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/annotations/image.py", line 19, in <module>
    from pdf_annotate.annotations.rect import RectAnnotation
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/annotations/rect.py", line 12, in <module>
    from pdf_annotate.config.appearance import set_appearance_state
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/config/appearance.py", line 26, in <module>
    from pdf_annotate.graphics import ContentStream
  File "/Users/myusername/Library/Python/2.7/lib/python/site-packages/pdf_annotate/graphics.py", line 130
    new_parents = (*parents, BaseCommand, namedtuple_klass)
                   ^
SyntaxError: invalid syntax

Any idea what I'm doing wrong?

[jonls]

It looks like you are trying to use Python 2.7. This library requires Python 3.5 or later.