###Instructions

A time period starting from ```'hh:mm'``` lasting until ```'hh:mm'``` is stored in an array:
```
['08:14', '11:34']
```
A set of different time periods is then stored in a 2D Array like so, each in its own sub-array:
```
[['08:14','11:34'], ['08:16','08:18'], ['22:18','01:14'], ['09:30','10:32'], ['04:23','05:11'], ['11:48','13:48'], ['01:12','01:14'], ['01:13','08:15']]
```
Write a function that will take a 2D Array like the above as argument and return a 2D Array of the argument's sub-arrays sorted in ascending order.

Take note of the following:

* The first time period starts at the earliest time  possible ```('00:00'+)```.
* The next time period is the one that starts the soonest **after** the prior time period finishes. If several time periods begin at the same hour, pick the first one showing up in the original array.
* The next time period can start the same time the last one finishes.

This:
```
[['08:14','11:34'], ['08:16','08:18'], ['13:48','01:14'], ['09:30','10:32'], ['04:23','05:11'], ['11:48','13:48'], ['01:12','01:14'], ['01:13','08:15']]
```
Should return:
```
[['01:12','01:14'], ['04:23','05:11'], ['08:14','11:34'], ['11:48','13:48'], ['13:48','01:14'], ['08:16','08:18'], ['09:30','10:32'], ['01:13','08:15']]
```

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

def _disabled_input(*args, **kwargs):
    raise RuntimeError("input() is disabled in callable mode")
builtins.input = _disabled_input

ns = {"__name__": "__judge__"}  # prevent if __name__ == "__main__" blocks
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = 'def sort_time(arr):\n    arr = sorted(arr, key = lambda x: x[0])\n    out = [["", "00:00"]]\n    \n    while arr:\n        i = next((i for i,t in enumerate(arr) if t[0] >= out[-1][1]), None)\n        out.append(arr.pop(i if i else 0))\n\n    return out[1:]'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'sort_time'
if _fn_name:
    if "Solution" in ns:
        try:
            _obj = ns["Solution"]()
            if hasattr(_obj, _fn_name):
                _target = getattr(_obj, _fn_name)
        except Exception:
            _target = None
    if _target is None and _fn_name in ns and callable(ns[_fn_name]):
        _target = ns[_fn_name]
# Fallback: if there's exactly one user-defined function, use it
if _target is None:
    _cands = [v for k, v in ns.items() if callable(v) and getattr(v, "__module__", "") in ("__judge__", "__main__")]
    _user_funcs = [c for c in _cands if getattr(c, "__name__", "").startswith("_") is False]
    if len(_user_funcs) == 1:
        _target = _user_funcs[0]
if _target is None:
    raise RuntimeError(f"Could not resolve callable '{_fn_name}'")

_raw = sys.stdin.read().strip()
if _raw:
    _parsed = json.loads(_raw)
    if isinstance(_parsed, dict):
        _kwargs = _parsed.get("kwargs", {})
        _args = _parsed.get("args", [])
    else:
        _args, _kwargs = _parsed, {}
else:
    _args, _kwargs = [], {}
if not isinstance(_args, (list, tuple)):
    _args = [_args]
_res = _target(*_args, **_kwargs)
try:
    sys.stdout.write(repr(_res) + "\n")
except Exception:
    pass

```

Measured memory_bytes: 6248