openpyxl.drawing.graphicGroupTransform2D fails on instantiate
*Created originally on Bitbucket by [jusdino (Justin Frahm)](https://bitbucket.org/%7B0cdb477a-976c-402e-8bb9-1bbccc8e3c54%7D/)*
Instantiating a GroupTransform2D results in an exception:
from openpyxl.drawing.graphic import GroupTransform2D
gt = GroupTransform2D()
Python 3.6 stack trace:
Traceback (most recent call last):
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/descriptors/base.py", line 57, in _convert
value = expected_type(value)
TypeError: int() argument must be a string, a bytes-like object or a number, not 'NoneType'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<input>", line 1, in <module>
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/drawing/graphic.py", line 53, in __init__
self.rot = rot
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/descriptors/base.py", line 69, in __set__
value = _convert(self.expected_type, value)
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/descriptors/base.py", line 59, in _convert
raise TypeError('expected ' + str(expected_type))
TypeError: expected <class 'int'>
Python 2.7 stack trace:
Traceback (most recent call last):
File "<input>", line 1, in <module>
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/drawing/graphic.py", line 53, in __init__
self.rot = rot
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/descriptors/base.py", line 69, in __set__
value = _convert(self.expected_type, value)
File "/home/jusdino/ownCloud/Documents/eclipse/openpyxl/openpyxl/descriptors/base.py", line 59, in _convert
raise TypeError('expected ' + str(expected_type))
TypeError: expected <type 'long'>
This happens when using 2.5, 2.6, and Default branches.
*Attachments:* [dct_clean.xlsm](/uploads/73004d35dffefa74c47c6fb91789d299/dct_clean.xlsm)
issue