diff --git a/tests/snippets/stdlib_io_bytesio.py b/tests/snippets/stdlib_io_bytesio.py
index f6f97e684..571444876 100644
--- a/tests/snippets/stdlib_io_bytesio.py
+++ b/tests/snippets/stdlib_io_bytesio.py
@@ -7,6 +7,7 @@ def test_01():
     f = BytesIO()
     f.write(bytes_string)
 
+    assert f.tell() == len(bytes_string)
     assert f.getvalue() == bytes_string
 
 def test_02():
@@ -39,12 +40,41 @@ def test_04():
     f = BytesIO(string)
 
     assert f.read(4) == b'Test'
+    assert f.tell() == 4
     assert f.seek(0) == 0
     assert f.read(4) == b'Test'
 
+def test_05():
+    """
+        Tests that the write method accpets bytearray
+    """
+    bytes_string =  b'Test String 5'
+
+    f = BytesIO()
+    f.write(bytearray(bytes_string))
+
+    assert f.getvalue() == bytes_string
+
+
+def test_06():
+    """
+        Tests readline
+    """
+    bytes_string =  b'Test String 6\nnew line is here\nfinished'
+
+    f = BytesIO(bytes_string)
+
+    assert f.readline() == b'Test String 6\n'
+    assert f.readline() == b'new line is here\n'
+    assert f.readline() == b'finished'
+    assert f.readline() == b''
+
+
 if __name__ == "__main__":
     test_01()
     test_02()
     test_03()
     test_04()
+    test_05()
+    test_06()
 
diff --git a/tests/snippets/stdlib_io_stringio.py b/tests/snippets/stdlib_io_stringio.py
index 0b4182527..828f0506e 100644
--- a/tests/snippets/stdlib_io_stringio.py
+++ b/tests/snippets/stdlib_io_stringio.py
@@ -10,6 +10,7 @@ def test_01():
     f = StringIO()
     f.write(string)
 
+    assert f.tell() == len(string)
     assert f.getvalue() == string
 
 def test_02():
@@ -46,11 +47,26 @@ def test_04():
     f = StringIO(string)
 
     assert f.read(4) == 'Test'
+    assert f.tell() == 4
     assert f.seek(0) == 0
     assert f.read(4) == 'Test'
 
+def test_05():
+    """
+        Tests readline
+    """
+    string =  'Test String 6\nnew line is here\nfinished'
+
+    f = StringIO(string)
+
+    assert f.readline() == 'Test String 6\n'
+    assert f.readline() == 'new line is here\n'
+    assert f.readline() == 'finished'
+    assert f.readline() == ''
+
 if __name__ == "__main__":
     test_01()
     test_02()
     test_03()
     test_04()
+    test_05()
diff --git a/vm/src/stdlib/io.rs b/vm/src/stdlib/io.rs
index bee7e1d7f..87ab1dcd4 100644
--- a/vm/src/stdlib/io.rs
+++ b/vm/src/stdlib/io.rs
@@ -11,6 +11,7 @@ use num_traits::ToPrimitive;
 use super::os;
 use crate::function::{OptionalArg, OptionalOption, PyFuncArgs};
 use crate::obj::objbytearray::PyByteArray;
+use crate::obj::objbyteinner::PyBytesLike;
 use crate::obj::objbytes;
 use crate::obj::objbytes::PyBytes;
 use crate::obj::objint::{self, PyIntRef};
@@ -81,6 +82,19 @@ impl BufferedIO {
 
         Some(buffer)
     }
+
+    fn tell(&self) -> u64 {
+        self.cursor.position()
+    }
+
+    fn readline(&mut self) -> Option<String> {
+        let mut buf = String::new();
+
+        match self.cursor.read_line(&mut buf) {
+            Ok(_) => Some(buf),
+            Err(_) => None,
+        }
+    }
 }
 
 #[derive(Debug)]
@@ -141,6 +155,17 @@ impl PyStringIORef {
             Err(_) => Err(vm.new_value_error("Error Retrieving Value".to_string())),
         }
     }
+
+    fn tell(self, _vm: &VirtualMachine) -> u64 {
+        self.buffer.borrow().tell()
+    }
+
+    fn readline(self, vm: &VirtualMachine) -> PyResult<String> {
+        match self.buffer.borrow_mut().readline() {
+            Some(line) => Ok(line),
+            None => Err(vm.new_value_error("Error Performing Operation".to_string())),
+        }
+    }
 }
 
 fn string_io_new(
@@ -173,11 +198,11 @@ impl PyValue for PyBytesIO {
 }
 
 impl PyBytesIORef {
-    fn write(self, data: objbytes::PyBytesRef, vm: &VirtualMachine) -> PyResult {
-        let bytes = data.get_value();
+    fn write(self, data: PyBytesLike, vm: &VirtualMachine) -> PyResult<u64> {
+        let bytes = data.to_cow();
 
-        match self.buffer.borrow_mut().write(bytes) {
-            Some(value) => Ok(vm.ctx.new_int(value)),
+        match self.buffer.borrow_mut().write(&bytes) {
+            Some(value) => Ok(value),
             None => Err(vm.new_type_error("Error Writing Bytes".to_string())),
         }
     }
@@ -207,6 +232,17 @@ impl PyBytesIORef {
     fn seekable(self, _vm: &VirtualMachine) -> bool {
         true
     }
+
+    fn tell(self, _vm: &VirtualMachine) -> u64 {
+        self.buffer.borrow().tell()
+    }
+
+    fn readline(self, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
+        match self.buffer.borrow_mut().readline() {
+            Some(line) => Ok(line.as_bytes().to_vec()),
+            None => Err(vm.new_value_error("Error Performing Operation".to_string())),
+        }
+    }
 }
 
 fn bytes_io_new(
@@ -720,7 +756,9 @@ pub fn make_module(vm: &VirtualMachine) -> PyObjectRef {
         "seekable" => ctx.new_rustfunc(PyStringIORef::seekable),
         "read" => ctx.new_rustfunc(PyStringIORef::read),
         "write" => ctx.new_rustfunc(PyStringIORef::write),
-        "getvalue" => ctx.new_rustfunc(PyStringIORef::getvalue)
+        "getvalue" => ctx.new_rustfunc(PyStringIORef::getvalue),
+        "tell" => ctx.new_rustfunc(PyStringIORef::tell),
+        "readline" => ctx.new_rustfunc(PyStringIORef::readline),
     });
 
     //BytesIO: in-memory bytes
@@ -731,7 +769,9 @@ pub fn make_module(vm: &VirtualMachine) -> PyObjectRef {
         "seek" => ctx.new_rustfunc(PyBytesIORef::seek),
         "seekable" => ctx.new_rustfunc(PyBytesIORef::seekable),
         "write" => ctx.new_rustfunc(PyBytesIORef::write),
-        "getvalue" => ctx.new_rustfunc(PyBytesIORef::getvalue)
+        "getvalue" => ctx.new_rustfunc(PyBytesIORef::getvalue),
+        "tell" => ctx.new_rustfunc(PyBytesIORef::tell),
+        "readline" => ctx.new_rustfunc(PyBytesIORef::readline),
     });
 
     py_module!(vm, "_io", {