Exception in TextLine.copy()

from expyriment.stimuli import TextLine
t = TextLine('test')
t.present()
t2 = t.copy()

Traceback (most recent call last):
  File "/home/sebastiaan/git/opensesame/libopensesame/inline_script.py", line 121, in run
    exec(self.crun)
  File "<string>", line 4, in <module>
  File "/home/sebastiaan/python-libs/expyriment/stimuli/_visual.py", line 318, in copy
    rtn = Stimulus.copy(self)
  File "/home/sebastiaan/python-libs/expyriment/stimuli/_stimulus.py", line 58, in copy
    copy = deepcopy(self)
  File "/usr/lib/python2.7/copy.py", line 190, in deepcopy
    y = _reconstruct(x, rv, 1, memo)
  File "/usr/lib/python2.7/copy.py", line 334, in _reconstruct
    state = deepcopy(state, memo)
  File "/usr/lib/python2.7/copy.py", line 163, in deepcopy
    y = copier(x, memo)
  File "/usr/lib/python2.7/copy.py", line 257, in _deepcopy_dict
    y[deepcopy(key, memo)] = deepcopy(value, memo)
  File "/usr/lib/python2.7/copy.py", line 190, in deepcopy
    y = _reconstruct(x, rv, 1, memo)
  File "/usr/lib/python2.7/copy.py", line 329, in _reconstruct
    y = callable(*args)
  File "/usr/lib/python2.7/copy_reg.py", line 93, in __newobj__
    return cls.__new__(cls, *args)
TypeError: object.__new__(pygame.font.Font) is not safe, use pygame.font.Font.__new__()