In [2]: from pygmt.params import Position

In [3]: Position((1, 0), cstype="invalid")
Out[3]: Position(refpoint=(1, 0), cstype='invalid')

In [1]: from pygmt.params import Position

In [2]: Position((1, 0), cstype="invalid")
---------------------------------------------------------------------------
GMTValueError                             Traceback (most recent call last)
Cell In[2], line 1
----> 1 Position((1, 0), cstype="invalid")

File <string>:7, in __init__(self, refpoint, cstype, anchor, offset)

File ~/OSS/gmt/pygmt/pygmt/params/base.py:61, in BaseParam.__post_init__(self)
     57 def __post_init__(self):
     58     """
     59     Post-initialization method to _validate the _aliases property.
     60     """
---> 61     self._validate()

File ~/OSS/gmt/pygmt/pygmt/params/position.py:190, in Position._validate(self)
    184             raise GMTValueError(
    185                 self.refpoint,
    186                 description="reference point",
    187                 reason="Expect a valid 2-character justification code.",
    188             )
    189     case _:
--> 190         raise GMTValueError(
    191             self.cstype,
    192             description="cstype",
    193             choices=[
    194                 "mapcoords",
    195                 "plotcoords",
    196                 "boxcoords",
    197                 "inside",
    198                 "outside",
    199             ],
    200         )
    201 # Validate the anchor if specified.
    202 if self.anchor is not None and self.anchor not in _valid_anchors:

GMTValueError: Invalid cstype: 'invalid'. Expected one of: 'mapcoords', 'plotcoords', 'boxcoords', 'inside', 'outside'.