fix: compatible with python3.8 (#234)

Author: aisk

pydruid/query.py

@@ -14,8 +14,8 @@
 # limitations under the License.
 #
 
-import collections
 import json
+from collections.abc import MutableSequence
 
 from pydruid.utils.aggregators import build_aggregators
 from pydruid.utils.dimensions import build_dimension
@@ -25,7 +25,7 @@
 from pydruid.utils.query_utils import UnicodeWriter
 
 
-class Query(collections.abc.MutableSequence):
+class Query(MutableSequence):
     """
     Query objects are produced by PyDruid clients and can be used for
     exporting query results into TSV files or