Fix issue 18434

MultiIndex.from_tuples accept zipped tuples in python 3. Compatibility
between 2 and 3.

doc/source/whatsnew/v0.22.0.txt

@@ -137,6 +137,7 @@ Indexing
 - Bug in :func:`Series.truncate` which raises ``TypeError`` with a monotonic ``PeriodIndex`` (:issue:`17717`)
 - Bug in :func:`DataFrame.groupby` where tuples were interpreted as lists of keys rather than as keys (:issue:`17979`, :issue:`18249`)
 - Bug in :func:`MultiIndex.remove_unused_levels`` which would fill nan values (:issue:`18417`)
+- Bug in :func:`MultiIndex.from_tuples`` which would fail to take zipped tuples in python3 (:issue:`18434`)
 -
 
 I/O

pandas/core/indexes/multi.py

@@ -1206,6 +1206,12 @@ def from_tuples(cls, tuples, sortorder=None, names=None):
         MultiIndex.from_product : Make a MultiIndex from cartesian product
                                   of iterables
         """
+        if not hasattr(tuples, '__len__'):
+            try:
+                iter(tuples)  # if iterable, then it's iterator or generator
+            except TypeError:
+                raise TypeError('Inappropriate input for tuples.')
+            tuples = list(tuples)
         if len(tuples) == 0:
             if names is None:
                 msg = 'Cannot infer number of levels from empty list'