>>> import struct
>>> data = struct.pack('>i4sh', 7, 'spam', 8)
Traceback (most recent call last):
  File "<pyshell#56>", line 1, in <module>
    data = struct.pack('>i4sh', 7, 'spam', 8)
struct.error: argument for 's' must be a bytes object
>>> F = open('data.bin', 'wb')
>>> import struct
>>> data = struct.pack('>i4sh', 7, 'spam', 8)
Traceback (most recent call last):
  File "<pyshell#59>", line 1, in <module>
    data = struct.pack('>i4sh', 7, 'spam', 8)
struct.error: argument for 's' must be a bytes object
>>> data = struct.pack(r'>i4sh', 7 , r'spam', 8)
Traceback (most recent call last):
  File "<pyshell#60>", line 1, in <module>
    data = struct.pack(r'>i4sh', 7 , r'spam', 8)
struct.error: argument for 's' must be a bytes object
>>> data = struct.pack('>i4h', 7, 'spam', 8)
Traceback (most recent call last):
  File "<pyshell#61>", line 1, in <module>
    data = struct.pack('>i4h', 7, 'spam', 8)
struct.error: pack requires exactly 5 arguments
>>> data = struct.pack('>i4h', 7, 1, 'spam', 8)
Traceback (most recent call last):
  File "<pyshell#62>", line 1, in <module>
    data = struct.pack('>i4h', 7, 1, 'spam', 8)
struct.error: pack requires exactly 5 arguments
>>> data = struct.pack(7, 1, 8)
Traceback (most recent call last):
  File "<pyshell#63>", line 1, in <module>
    data = struct.pack(7, 1, 8)
TypeError: Struct() argument 1 must be a bytes object, not int
>>> data = struct.pack('spam', 7, 1, 8)
Traceback (most recent call last):
  File "<pyshell#64>", line 1, in <module>
    data = struct.pack('spam', 7, 1, 8)
struct.error: bad char in struct format
>>> data = struct.pack('>i4')
Traceback (most recent call last):
  File "<pyshell#65>", line 1, in <module>
    data = struct.pack('>i4')
struct.error: repeat count given without format specifier
>>> data = struct.pack('>i4h')
Traceback (most recent call last):
  File "<pyshell#66>", line 1, in <module>
    data = struct.pack('>i4h')
struct.error: pack requires exactly 5 arguments
>>> data = struct.pack('>i4h', '>i4h',  '>i4h', '>i4h',  '>i4h', )
Traceback (most recent call last):
  File "<pyshell#67>", line 1, in <module>
    data = struct.pack('>i4h', '>i4h',  '>i4h', '>i4h',  '>i4h', )
struct.error: pack requires exactly 5 arguments

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