def METHOD_NAME(cls, glayers_obj: dict[StrictStr, StrictStr]):
    """checks glayers to ensure valid keys,type. Glayers must be passed as dict[str,str]"""
    for glayer, mapped_layer in glayers_obj.items():
        if (not isinstance(glayer, str)) or (not isinstance(mapped_layer, str)):
            raise TypeError("glayers should be passed as dict[str, str]")
        if glayer not in cls.valid_glayers:
            raise ValueError(
                "glayers keys must be one of generic layers listed in class variable valid_glayers"
            )
    return glayers_obj