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venv/Lib/site-packages/sqlalchemy/dialects/postgresql/pypostgresql.py

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+# postgresql/pypostgresql.py
+# Copyright (C) 2005-2019 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+"""
+.. dialect:: postgresql+pypostgresql
+    :name: py-postgresql
+    :dbapi: pypostgresql
+    :connectstring: postgresql+pypostgresql://user:password@host:port/dbname[?key=value&key=value...]
+    :url: http://python.projects.pgfoundry.org/
+
+
+"""  # noqa
+
+from .base import PGDialect
+from .base import PGExecutionContext
+from ... import processors
+from ... import types as sqltypes
+from ... import util
+
+
+class PGNumeric(sqltypes.Numeric):
+    def bind_processor(self, dialect):
+        return processors.to_str
+
+    def result_processor(self, dialect, coltype):
+        if self.asdecimal:
+            return None
+        else:
+            return processors.to_float
+
+
+class PGExecutionContext_pypostgresql(PGExecutionContext):
+    pass
+
+
+class PGDialect_pypostgresql(PGDialect):
+    driver = "pypostgresql"
+
+    supports_unicode_statements = True
+    supports_unicode_binds = True
+    description_encoding = None
+    default_paramstyle = "pyformat"
+
+    # requires trunk version to support sane rowcounts
+    # TODO: use dbapi version information to set this flag appropriately
+    supports_sane_rowcount = True
+    supports_sane_multi_rowcount = False
+
+    execution_ctx_cls = PGExecutionContext_pypostgresql
+    colspecs = util.update_copy(
+        PGDialect.colspecs,
+        {
+            sqltypes.Numeric: PGNumeric,
+            # prevents PGNumeric from being used
+            sqltypes.Float: sqltypes.Float,
+        },
+    )
+
+    @classmethod
+    def dbapi(cls):
+        from postgresql.driver import dbapi20
+
+        return dbapi20
+
+    _DBAPI_ERROR_NAMES = [
+        "Error",
+        "InterfaceError",
+        "DatabaseError",
+        "DataError",
+        "OperationalError",
+        "IntegrityError",
+        "InternalError",
+        "ProgrammingError",
+        "NotSupportedError",
+    ]
+
+    @util.memoized_property
+    def dbapi_exception_translation_map(self):
+        if self.dbapi is None:
+            return {}
+
+        return dict(
+            (getattr(self.dbapi, name).__name__, name)
+            for name in self._DBAPI_ERROR_NAMES
+        )
+
+    def create_connect_args(self, url):
+        opts = url.translate_connect_args(username="user")
+        if "port" in opts:
+            opts["port"] = int(opts["port"])
+        else:
+            opts["port"] = 5432
+        opts.update(url.query)
+        return ([], opts)
+
+    def is_disconnect(self, e, connection, cursor):
+        return "connection is closed" in str(e)
+
+
+dialect = PGDialect_pypostgresql