Bump tempora from 5.1.0 to 5.2.1 (#1977)

* Bump tempora from 5.1.0 to 5.2.1

Bumps [tempora](https://github.com/jaraco/tempora) from 5.1.0 to 5.2.1.
- [Release notes](https://github.com/jaraco/tempora/releases)
- [Changelog](https://github.com/jaraco/tempora/blob/main/CHANGES.rst)
- [Commits](https://github.com/jaraco/tempora/compare/v5.1.0...v5.2.1)

---
updated-dependencies:
- dependency-name: tempora
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* Update tempora==5.2.1

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: JonnyWong16 <9099342+JonnyWong16@users.noreply.github.com>

[skip ci]

lib/more_itertools/more.py

@@ -68,6 +68,7 @@ __all__ = [
     'exactly_n',
     'filter_except',
     'first',
+    'gray_product',
     'groupby_transform',
     'ichunked',
     'iequals',
@@ -658,6 +659,7 @@ def distinct_permutations(iterable, r=None):
         [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
 
     """
+
     # Algorithm: https://w.wiki/Qai
     def _full(A):
         while True:
@@ -1301,7 +1303,7 @@ def split_at(iterable, pred, maxsplit=-1, keep_separator=False):
         [[0], [2], [4, 5, 6, 7, 8, 9]]
 
     By default, the delimiting items are not included in the output.
-    The include them, set *keep_separator* to ``True``.
+    To include them, set *keep_separator* to ``True``.
 
         >>> list(split_at('abcdcba', lambda x: x == 'b', keep_separator=True))
         [['a'], ['b'], ['c', 'd', 'c'], ['b'], ['a']]
@@ -1391,7 +1393,9 @@ def split_after(iterable, pred, maxsplit=-1):
         if pred(item) and buf:
             yield buf
             if maxsplit == 1:
-                yield list(it)
+                buf = list(it)
+                if buf:
+                    yield buf
                 return
             buf = []
             maxsplit -= 1
@@ -2914,6 +2918,7 @@ def make_decorator(wrapping_func, result_index=0):
         '7'
 
     """
+
     # See https://sites.google.com/site/bbayles/index/decorator_factory for
     # notes on how this works.
     def decorator(*wrapping_args, **wrapping_kwargs):
@@ -3464,7 +3469,6 @@ def _sample_unweighted(iterable, k):
     next_index = k + floor(log(random()) / log(1 - W))
 
     for index, element in enumerate(iterable, k):
-
         if index == next_index:
             reservoir[randrange(k)] = element
             # The new W is the largest in a sample of k U(0, `old_W`) numbers
@@ -4284,7 +4288,6 @@ def minmax(iterable_or_value, *others, key=None, default=_marker):
         lo_key = hi_key = key(lo)
 
         for x, y in zip_longest(it, it, fillvalue=lo):
-
             x_key, y_key = key(x), key(y)
 
             if y_key < x_key:
@@ -4345,3 +4348,45 @@ def constrained_batches(
 
     if batch:
         yield tuple(batch)
+
+
+def gray_product(*iterables):
+    """Like :func:`itertools.product`, but return tuples in an order such
+    that only one element in the generated tuple changes from one iteration
+    to the next.
+
+        >>> list(gray_product('AB','CD'))
+        [('A', 'C'), ('B', 'C'), ('B', 'D'), ('A', 'D')]
+
+    This function consumes all of the input iterables before producing output.
+    If any of the input iterables have fewer than two items, ``ValueError``
+    is raised.
+
+    For information on the algorithm, see
+    `this section <https://www-cs-faculty.stanford.edu/~knuth/fasc2a.ps.gz>`__
+    of Donald Knuth's *The Art of Computer Programming*.
+    """
+    all_iterables = tuple(tuple(x) for x in iterables)
+    iterable_count = len(all_iterables)
+    for iterable in all_iterables:
+        if len(iterable) < 2:
+            raise ValueError("each iterable must have two or more items")
+
+    # This is based on "Algorithm H" from section 7.2.1.1, page 20.
+    # a holds the indexes of the source iterables for the n-tuple to be yielded
+    # f is the array of "focus pointers"
+    # o is the array of "directions"
+    a = [0] * iterable_count
+    f = list(range(iterable_count + 1))
+    o = [1] * iterable_count
+    while True:
+        yield tuple(all_iterables[i][a[i]] for i in range(iterable_count))
+        j = f[0]
+        f[0] = 0
+        if j == iterable_count:
+            break
+        a[j] = a[j] + o[j]
+        if a[j] == 0 or a[j] == len(all_iterables[j]) - 1:
+            o[j] = -o[j]
+            f[j] = f[j + 1]
+            f[j + 1] = j + 1