refactor: remove unused import from errors module in dataframe.rs

Author: kosiew

src/dataframe.rs

@@ -46,15 +46,14 @@ use pyo3::pybacked::PyBackedStr;
 use pyo3::types::{PyCapsule, PyList, PyTuple, PyTupleMethods};
 use pyo3::PyErr;
 
-use crate::errors::{py_datafusion_err, to_datafusion_err, PyDataFusionError};
+use crate::errors::{py_datafusion_err, PyDataFusionError};
 use crate::expr::sort_expr::to_sort_expressions;
 use crate::physical_plan::PyExecutionPlan;
 use crate::record_batch::{poll_next_batch, PyRecordBatchStream};
 use crate::sql::logical::PyLogicalPlan;
 use crate::table::{PyTable, TempViewTable};
 use crate::utils::{
-    get_tokio_runtime, is_ipython_env, py_obj_to_scalar_value, spawn_future, validate_pycapsule,
-    wait_for_future,
+    is_ipython_env, py_obj_to_scalar_value, spawn_future, validate_pycapsule, wait_for_future,
 };
 use crate::{
     errors::PyDataFusionResult,