'Add header to table. This is a number of texts to be put at
the top of the table. They will replace an existing header.
Args:
args (str): These strings will be used as the header texts.
Kwargs:
Same keywords as per `EvTable.__init__`. Will be applied
to the new header\'s cells.'

def add_header(self, *args, **kwargs):

    self.header = True
    self.add_row(ypos=0, *args, **kwargs)
