Revert "Merge "add aiomysql support""

This reverts commit 23343f87f3297ad31d7315ac0e5312db10ef7592, reversing
changes made to c5831b1abd98c46ef7eab7ee82ead18756aea112.

The crashes that occur in jenkins have not been solved and are
now impacting master.   I am not able to reproduce the failure,
including running on the CI machines directly, and a few runs
where I sat there for 20 minutes and watched, it didn't happen.
it is the ultimate heisenbug.

Additionally, there's a reference to "arraysize" that doesn't
exist in fetchmany() and there seem to be no tests that exercise
this for any DBAPI which is also a major bug to be fixed.

References: #5747

1 files changed, 4 insertions, 13 deletions

diff --git a/lib/sqlalchemy/dialects/mysql/mysqldb.py b/lib/sqlalchemy/dialects/mysql/mysqldb.py
index 605407f46..b20e061fb 100644
--- a/lib/sqlalchemy/dialects/mysql/mysqldb.py
+++ b/lib/sqlalchemy/dialects/mysql/mysqldb.py
@@ -211,25 +211,16 @@ class MySQLDialect_mysqldb(MySQLDialect):
         # FOUND_ROWS must be set in CLIENT_FLAGS to enable
         # supports_sane_rowcount.
         client_flag = opts.get("client_flag", 0)
-
-        client_flag_found_rows = self._found_rows_client_flag()
-        if client_flag_found_rows is not None:
-            client_flag |= client_flag_found_rows
-            opts["client_flag"] = client_flag
-        return [[], opts]
-
-    def _found_rows_client_flag(self):
         if self.dbapi is not None:
             try:
                 CLIENT_FLAGS = __import__(
                     self.dbapi.__name__ + ".constants.CLIENT"
                 ).constants.CLIENT
+                client_flag |= CLIENT_FLAGS.FOUND_ROWS
             except (AttributeError, ImportError):
-                return None
-            else:
-                return CLIENT_FLAGS.FOUND_ROWS
-        else:
-            return None
+                self.supports_sane_rowcount = False
+            opts["client_flag"] = client_flag
+        return [[], opts]
 
     def _extract_error_code(self, exception):
         return exception.args[0]