*idx* is a required attribute of a c:pt element, but must be specified when pt is None, as when a "placeholder" category is created to represent a missing c:pt element.
(self, pt, idx=None)
| 154 | return str.__new__(cls, category_label) |
| 155 | |
| 156 | def __init__(self, pt, idx=None): |
| 157 | """ |
| 158 | *idx* is a required attribute of a c:pt element, but must be |
| 159 | specified when pt is None, as when a "placeholder" category is |
| 160 | created to represent a missing c:pt element. |
| 161 | """ |
| 162 | self._element = self._pt = pt |
| 163 | self._idx = idx |
| 164 | |
| 165 | @property |
| 166 | def idx(self): |