diff --git a/format/src/bigint.rs b/format/src/bigint.rs
new file mode 100644
index 00000000..ed12ec44
--- /dev/null
+++ b/format/src/bigint.rs
@@ -0,0 +1,4 @@
+#[cfg(feature = "malachite-bigint")]
+pub use malachite_bigint::{BigInt, Sign};
+#[cfg(feature = "num-bigint")]
+pub use num_bigint::{BigInt, Sign};
diff --git a/format/src/cformat.rs b/format/src/cformat.rs
index 248ad514..975da4be 100644
--- a/format/src/cformat.rs
+++ b/format/src/cformat.rs
@@ -1,10 +1,7 @@
 //! Implementation of Printf-Style string formatting
 //! as per the [Python Docs](https://docs.python.org/3/library/stdtypes.html#printf-style-string-formatting).
+use crate::bigint::{BigInt, Sign};
 use bitflags::bitflags;
-#[cfg(feature = "malachite-bigint")]
-use malachite_bigint::{BigInt, Sign};
-#[cfg(feature = "num-bigint")]
-use num_bigint::{BigInt, Sign};
 use num_traits::Signed;
 use rustpython_literal::{float, format::Case};
 use std::{
diff --git a/format/src/format.rs b/format/src/format.rs
index 8109f1f9..fd497b90 100644
--- a/format/src/format.rs
+++ b/format/src/format.rs
@@ -1,8 +1,5 @@
+use crate::bigint::{BigInt, Sign};
 use itertools::{Itertools, PeekingNext};
-#[cfg(feature = "malachite-bigint")]
-use malachite_bigint::{BigInt, Sign};
-#[cfg(feature = "num-bigint")]
-use num_bigint::{BigInt, Sign};
 use num_traits::FromPrimitive;
 use num_traits::{cast::ToPrimitive, Signed};
 use rustpython_literal::float;
diff --git a/format/src/lib.rs b/format/src/lib.rs
index 3c5d8695..acf8e1b3 100644
--- a/format/src/lib.rs
+++ b/format/src/lib.rs
@@ -1,3 +1,4 @@
+mod bigint;
 pub mod cformat;
 mod format;