Struct error required argument is not an integer

def __init__(self):
    set_data = {}
    set_data["db_ip"] = "127.0.0.1"
    set_data["db_name"] = "***db name***"
    set_data["db_user"] = "***db user***
    set_data["db_pass"] = "***db password**!"
    set_data["db_port"] = 3306
    engine_str = (
        "mysql+pymysql://"
        + set_data["db_user"]
        + ":"
        + set_data["db_pass"]
        + "@"
        + set_data["db_ip"]
        + ":" + str(set_data["db_port"])
        + "/"
        + set_data["db_name"]
        )

    engine = create_engine(
        engine_str,
        pool_size=10,
        max_overflow=20,
        pool_pre_ping=True,
        pool_recycle=1100
    )

    self.metadata = MetaData(bind=engine)
    self.session = scoped_session(sessionmaker(autocommit=False, autoflush=True, bind=engine))
    self.engine = engine
    conn = engine.connect()
    self.conn = conn

def session_scope_end(cbdb):
    logger.info("Closing Session Scope")
    try:
        yield cbdb.session
        cbdb.session.commit()
    except Exception as e:
        error = str(e)
        logger.warning(error)
        cbdb.session.rollback()
        raise
    finally:
        cbdb.session.close()
    cbdb.session.close()
    cbdb.engine.dispose()
    cbdb.conn.detach()
    cbdb.conn.close()
    return cbdb

Traceback (most recent call last):
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/pool/base.py", line 739, in _finalize_fairy
    fairy._reset(pool)
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/pool/base.py", line 988, in _reset
    pool._dialect.do_rollback(self)
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/engine/default.py", line 667, in do_rollback
    dbapi_connection.rollback()
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/pymysql/connections.py", line 479, in rollback
    self._execute_command(COMMAND.COM_QUERY, "ROLLBACK")
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/pymysql/connections.py", line 813, in _execute_command
    prelude = struct.pack("<iB", packet_size, command)
struct.error: required argument is not an integer
Exception closing connection <pymysql.connections.Connection object at 0x7f90f55cb250>
Traceback (most recent call last):
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/pool/base.py", line 739, in _finalize_fairy
    fairy._reset(pool)
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/pool/base.py", line 988, in _reset
    pool._dialect.do_rollback(self)
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/engine/default.py", line 667, in do_rollback
    dbapi_connection.rollback()
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/pymysql/connections.py", line 479, in rollback
    self._execute_command(COMMAND.COM_QUERY, "ROLLBACK")
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/pymysql/connections.py", line 813, in _execute_command
    prelude = struct.pack("<iB", packet_size, command)
struct.error: required argument is not an integer

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/pool/base.py", line 247, in _close_connection
    self._dialect.do_close(connection)
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/sqlalchemy/engine/default.py", line 673, in do_close
    dbapi_connection.close()
  File "/home/krypterro/PyApps/devbot/.venv/lib/python3.8/site-packages/pymysql/connections.py", line 408, in close
    send_data = struct.pack("<iB", 1, COMMAND.COM_QUIT)
struct.error: required argument is not an integer

7.1.2.1. Byte Order, Size, and Alignment¶

By default, C types are represented in the machine’s native format and byte
order, and properly aligned by skipping pad bytes if necessary (according to the
rules used by the C compiler).

Alternatively, the first character of the format string can be used to indicate
the byte order, size and alignment of the packed data, according to the
following table:

If the first character is not one of these, '@' is assumed.

Native byte order is big-endian or little-endian, depending on the host
system. For example, Intel x86 and AMD64 (x86-64) are little-endian;
Motorola 68000 and PowerPC G5 are big-endian; ARM and Intel Itanium feature
switchable endianness (bi-endian). Use sys.byteorder to check the
endianness of your system.

Native size and alignment are determined using the C compiler’s
sizeof expression. This is always combined with native byte order.

Standard size depends only on the format character; see the table in
the Format Characters section.

Note the difference between '@' and '=': both use native byte order, but
the size and alignment of the latter is standardized.

The form '!' is available for those poor souls who claim they can’t remember
whether network byte order is big-endian or little-endian.

There is no way to indicate non-native byte order (force byte-swapping); use the
appropriate choice of '<' or '>'.

Notes:

1. Padding is only automatically added between successive structure members.
   No padding is added at the beginning or the end of the encoded struct.
2. No padding is added when using non-native size and alignment, e.g.
   with ‘<’, ‘>’, ‘=’, and ‘!’.
3. To align the end of a structure to the alignment requirement of a
   particular type, end the format with the code for that type with a repeat
   count of zero. See Examples.

7.1.2.2. Format Characters¶

Format characters have the following meaning; the conversion between C and
Python values should be obvious given their types. The ‘Standard size’ column
refers to the size of the packed value in bytes when using standard size; that
is, when the format string starts with one of '<', '>', '!' or
'='. When using native size, the size of the packed value is
platform-dependent.

Changed in version 3.3: Added support for the 'n' and 'N' formats.

Changed in version 3.6: Added support for the 'e' format.

Notes:

1. The '?' conversion code corresponds to the _Bool type defined by
   C99. If this type is not available, it is simulated using a char. In
   standard mode, it is always represented by one byte.

2. The 'q' and 'Q' conversion codes are available in native mode only if
   the platform C compiler supports C long long, or, on Windows,
   __int64. They are always available in standard modes.

3. When attempting to pack a non-integer using any of the integer conversion
   codes, if the non-integer has a __index__() method then that method is
   called to convert the argument to an integer before packing.

   Changed in version 3.2: Use of the __index__() method for non-integers is new in 3.2.

4. The 'n' and 'N' conversion codes are only available for the native
   size (selected as the default or with the '@' byte order character).
   For the standard size, you can use whichever of the other integer formats
   fits your application.

5. For the 'f', 'd' and 'e' conversion codes, the packed
   representation uses the IEEE 754 binary32, binary64 or binary16 format (for
   'f', 'd' or 'e' respectively), regardless of the floating-point
   format used by the platform.

6. The 'P' format character is only available for the native byte ordering
   (selected as the default or with the '@' byte order character). The byte
   order character '=' chooses to use little- or big-endian ordering based
   on the host system. The struct module does not interpret this as native
   ordering, so the 'P' format is not available.

7. The IEEE 754 binary16 “half precision” type was introduced in the 2008
   revision of the IEEE 754 standard. It has a sign
   bit, a 5-bit exponent and 11-bit precision (with 10 bits explicitly stored),
   and can represent numbers between approximately 6.1e-05 and 6.5e+04
   at full precision. This type is not widely supported by C compilers: on a
   typical machine, an unsigned short can be used for storage, but not for math
   operations. See the Wikipedia page on the half-precision floating-point
   format for more information.

A format character may be preceded by an integral repeat count. For example,
the format string '4h' means exactly the same as 'hhhh'.

Whitespace characters between formats are ignored; a count and its format must
not contain whitespace though.

For the 's' format character, the count is interpreted as the length of the
bytes, not a repeat count like for the other format characters; for example,
'10s' means a single 10-byte string, while '10c' means 10 characters.
If a count is not given, it defaults to 1. For packing, the string is
truncated or padded with null bytes as appropriate to make it fit. For
unpacking, the resulting bytes object always has exactly the specified number
of bytes. As a special case, '0s' means a single, empty string (while
'0c' means 0 characters).

When packing a value x using one of the integer formats ('b',
'B', 'h', 'H', 'i', 'I', 'l', 'L',
'q', 'Q'), if x is outside the valid range for that format
then struct.error is raised.

Changed in version 3.1: In 3.0, some of the integer formats wrapped out-of-range values and
raised DeprecationWarning instead of struct.error.

The 'p' format character encodes a “Pascal string”, meaning a short
variable-length string stored in a fixed number of bytes, given by the count.
The first byte stored is the length of the string, or 255, whichever is
smaller. The bytes of the string follow. If the string passed in to
pack() is too long (longer than the count minus 1), only the leading
count-1 bytes of the string are stored. If the string is shorter than
count-1, it is padded with null bytes so that exactly count bytes in all
are used. Note that for unpack(), the 'p' format character consumes
count bytes, but that the string returned can never contain more than 255
bytes.

For the '?' format character, the return value is either True or
False. When packing, the truth value of the argument object is used.
Either 0 or 1 in the native or standard bool representation will be packed, and
any non-zero value will be True when unpacking.

7.1.2.3. Examples¶

A basic example of packing/unpacking three integers:

>>> from struct import *
>>> pack('hhl', 1, 2, 3)
b'x00x01x00x02x00x00x00x03'
>>> unpack('hhl', b'x00x01x00x02x00x00x00x03')
(1, 2, 3)
>>> calcsize('hhl')
8

Unpacked fields can be named by assigning them to variables or by wrapping
the result in a named tuple:

>>> record = b'raymond   x32x12x08x01x08'
>>> name, serialnum, school, gradelevel = unpack('<10sHHb', record)

>>> from collections import namedtuple
>>> Student = namedtuple('Student', 'name serialnum school gradelevel')
>>> Student._make(unpack('<10sHHb', record))
Student(name=b'raymond   ', serialnum=4658, school=264, gradelevel=8)

The ordering of format characters may have an impact on size since the padding
needed to satisfy alignment requirements is different:

>>> pack('ci', b'*', 0x12131415)
b'*x00x00x00x12x13x14x15'
>>> pack('ic', 0x12131415, b'*')
b'x12x13x14x15*'
>>> calcsize('ci')
8
>>> calcsize('ic')
5

The following format 'llh0l' specifies two pad bytes at the end, assuming
longs are aligned on 4-byte boundaries:

>>> pack('llh0l', 1, 2, 3)
b'x00x00x00x01x00x00x00x02x00x03x00x00'

This only works when native size and alignment are in effect; standard size and
alignment does not enforce any alignment.