in lib/metric-config-parser/metric_config_parser/data_source.py [0:0]
def from_expr_for(self, dataset: Optional[str]) -> str:
"""Expands the ``from_expression`` template for the given dataset.
If ``from_expression`` is not a template, returns ``from_expression``.
Args:
dataset (str or None): Dataset name to substitute
into the from expression.
"""
effective_dataset = dataset or self.default_dataset
if effective_dataset is None:
try:
return self.from_expression.format()
except Exception as e:
raise ValueError(
f"{self.name}: from_expression contains a dataset template but no value was provided." # noqa:E501
) from e
return self.from_expression.format(dataset=effective_dataset)