bin() 整数的二进制形式
内置函数 bin()，Python 官方文档描述如下：
help(bin)
Help on built-in function bin in module builtins:
bin(number, /)
Return the binary representation of an integer.
>>> bin(2796202)
'0b1010101010101010101010'
返回给定整数的二进制表示形式的字符串。
bin(123)
'0b1111011'
0b1111011
123
bool 返回对象的布尔值
内置函数（类） bool，Python 官方文档描述如下：
help(bool)
Help on class bool in module builtins:
class bool(int)
| bool(x) -> bool
|
| Returns True when the argument x is true, False otherwise.
| The builtins True and False are the only two instances of the class bool.
| The class bool is a subclass of the class int, and cannot be subclassed.
|
| Method resolution order:
| bool
| int
| object
|
| Methods defined here:
|
| __and__(self, value, /)
| Return self&value.
|
| __or__(self, value, /)
| Return self|value.
|
| __rand__(self, value, /)
| Return value&self.
|
| __repr__(self, /)
| Return repr(self).
|
| __ror__(self, value, /)
| Return value|self.
|
| __rxor__(self, value, /)
| Return value^self.
|
| __str__(self, /)
| Return str(self).
|
| __xor__(self, value, /)
| Return self^value.
|
| ----------------------------------------------------------------------
| Static methods defined here:
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| ----------------------------------------------------------------------
| Methods inherited from int:
|
| __abs__(self, /)
| abs(self)
|
| __add__(self, value, /)
| Return self+value.
|
| __bool__(self, /)
| self != 0
|
| __ceil__(...)
| Ceiling of an Integral returns itself.
|
| __divmod__(self, value, /)
| Return divmod(self, value).
|
| __eq__(self, value, /)
| Return self==value.
|
| __float__(self, /)
| float(self)
|
| __floor__(...)
| Flooring an Integral returns itself.
|
| __floordiv__(self, value, /)
| Return self//value.
|
| __format__(self, format_spec, /)
| Default object formatter.
|
| __ge__(self, value, /)
| Return self>=value.
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __getnewargs__(self, /)
|
| __gt__(self, value, /)
| Return self>value.
|
| __hash__(self, /)
| Return hash(self).
|
| __index__(self, /)
| Return self converted to an integer, if self is suitable for use as an index into a list.
|
| __int__(self, /)
| int(self)
|
| __invert__(self, /)
| ~self
|
| __le__(self, value, /)
| Return self<=value.
|
| __lshift__(self, value, /)
| Return self<<value.
|
| __lt__(self, value, /)
| Return self<value.
|
| __mod__(self, value, /)
| Return self%value.
|
| __mul__(self, value, /)
| Return self*value.
|
| __ne__(self, value, /)
| Return self!=value.
|
| __neg__(self, /)
| -self
|
| __pos__(self, /)
| +self
|
| __pow__(self, value, mod=None, /)
| Return pow(self, value, mod).
|
| __radd__(self, value, /)
| Return value+self.
|
| __rdivmod__(self, value, /)
| Return divmod(value, self).
|
| __rfloordiv__(self, value, /)
| Return value//self.
|
| __rlshift__(self, value, /)
| Return value<<self.
|
| __rmod__(self, value, /)
| Return value%self.
|
| __rmul__(self, value, /)
| Return value*self.
|
| __round__(...)
| Rounding an Integral returns itself.
| Rounding with an ndigits argument also returns an integer.
|
| __rpow__(self, value, mod=None, /)
| Return pow(value, self, mod).
|
| __rrshift__(self, value, /)
| Return value>>self.
|
| __rshift__(self, value, /)
| Return self>>value.
|
| __rsub__(self, value, /)
| Return value-self.
|
| __rtruediv__(self, value, /)
| Return value/self.
|
| __sizeof__(self, /)
| Returns size in memory, in bytes.
|
| __sub__(self, value, /)
| Return self-value.
|
| __truediv__(self, value, /)
| Return self/value.
|
| __trunc__(...)
| Truncating an Integral returns itself.
|
| bit_length(self, /)
| Number of bits necessary to represent self in binary.
|
| >>> bin(37)
| '0b100101'
| >>> (37).bit_length()
| 6
|
| conjugate(...)
| Returns self, the complex conjugate of any int.
|
| to_bytes(self, /, length, byteorder, *, signed=False)
| Return an array of bytes representing an integer.
|
| length
| Length of bytes object to use. An OverflowError is raised if the
| integer is not representable with the given number of bytes.
| byteorder
| The byte order used to represent the integer. If byteorder is 'big',
| the most significant byte is at the beginning of the byte array. If
| byteorder is 'little', the most significant byte is at the end of the
| byte array. To request the native byte order of the host system, use
| `sys.byteorder' as the byte order value.
| signed
| Determines whether two's complement is used to represent the integer.
| If signed is False and a negative integer is given, an OverflowError
| is raised.
|
| ----------------------------------------------------------------------
| Class methods inherited from int:
|
| from_bytes(bytes, byteorder, *, signed=False) from builtins.type
| Return the integer represented by the given array of bytes.
|
| bytes
| Holds the array of bytes to convert. The argument must either
| support the buffer protocol or be an iterable object producing bytes.
| Bytes and bytearray are examples of built-in objects that support the
| buffer protocol.
| byteorder
| The byte order used to represent the integer. If byteorder is 'big',
| the most significant byte is at the beginning of the byte array. If
| byteorder is 'little', the most significant byte is at the end of the
| byte array. To request the native byte order of the host system, use
| `sys.byteorder' as the byte order value.
| signed
| Indicates whether two's complement is used to represent the integer.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from int:
|
| denominator
| the denominator of a rational number in lowest terms
|
| imag
| the imaginary part of a complex number
|
| numerator
| the numerator of a rational number in lowest terms
|
| real
| the real part of a complex number
返回对象 x 的布尔值。省略 x 则返回 False。对象的真值、假值规则如下：
一个对象在默认情况下均被视为真值，除非当该对象被调用时其所属类定义了 __bool__() 方法且返回 False 或是定义了 __len__() 方法且返回零。
下面基本完整地列出了会被视为假值的内置对象:
- 被定义为假值的常量: None 和 False。
- 任何数值类型的零: 0, 0.0, 0j, Decimal(0), Fraction(0, 1)
- 空的序列和多项集: ‘’, (), [], {}, set(), range(0)
type(bool)
type
bool()
False
bool(None)
False
bool('0')
True
bool(' ')
True
bytes 创建 bytes 对象
内置函数（类）bytes，Python 官方文档描述如下：
help(bytes)
Help on class bytes in module builtins:
class bytes(object)
| bytes(iterable_of_ints) -> bytes
| bytes(string, encoding[, errors]) -> bytes
| bytes(bytes_or_buffer) -> immutable copy of bytes_or_buffer
| bytes(int) -> bytes object of size given by the parameter initialized with null bytes
| bytes() -> empty bytes object
|
| Construct an immutable array of bytes from:
| - an iterable yielding integers in range(256)
| - a text string encoded using the specified encoding
| - any object implementing the buffer API.
| - an integer
|
| Methods defined here:
|
| __add__(self, value, /)
| Return self+value.
|
| __contains__(self, key, /)
| Return key in self.
|
| __eq__(self, value, /)
| Return self==value.
|
| __ge__(self, value, /)
| Return self>=value.
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __getitem__(self, key, /)
| Return self[key].
|
| __getnewargs__(...)
|
| __gt__(self, value, /)
| Return self>value.
|
| __hash__(self, /)
| Return hash(self).
|
| __iter__(self, /)
| Implement iter(self).
|
| __le__(self, value, /)
| Return self<=value.
|
| __len__(self, /)
| Return len(self).
|
| __lt__(self, value, /)
| Return self<value.
|
| __mod__(self, value, /)
| Return self%value.
|
| __mul__(self, value, /)
| Return self*value.
|
| __ne__(self, value, /)
| Return self!=value.
|
| __repr__(self, /)
| Return repr(self).
|
| __rmod__(self, value, /)
| Return value%self.
|
| __rmul__(self, value, /)
| Return value*self.
|
| __str__(self, /)
| Return str(self).
|
| capitalize(...)
| B.capitalize() -> copy of B
|
| Return a copy of B with only its first character capitalized (ASCII)
| and the rest lower-cased.
|
| center(...)
| B.center(width[, fillchar]) -> copy of B
|
| Return B centered in a string of length width. Padding is
| done using the specified fill character (default is a space).
|
| count(...)
| B.count(sub[, start[, end]]) -> int
|
| Return the number of non-overlapping occurrences of subsection sub in
| bytes B[start:end]. Optional arguments start and end are interpreted
| as in slice notation.
|
| decode(self, /, encoding='utf-8', errors='strict')
| Decode the bytes using the codec registered for encoding.
|
| encoding
| The encoding with which to decode the bytes.
| errors
| The error handling scheme to use for the handling of decoding errors.
| The default is 'strict' meaning that decoding errors raise a
| UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
| as well as any other name registered with codecs.register_error that
| can handle UnicodeDecodeErrors.
|
| endswith(...)
| B.endswith(suffix[, start[, end]]) -> bool
|
| Return True if B ends with the specified suffix, False otherwise.
| With optional start, test B beginning at that position.
| With optional end, stop comparing B at that position.
| suffix can also be a tuple of bytes to try.
|
| expandtabs(...)
| B.expandtabs(tabsize=8) -> copy of B
|
| Return a copy of B where all tab characters are expanded using spaces.
| If tabsize is not given, a tab size of 8 characters is assumed.
|
| find(...)
| B.find(sub[, start[, end]]) -> int
|
| Return the lowest index in B where subsection sub is found,
| such that sub is contained within B[start,end]. Optional
| arguments start and end are interpreted as in slice notation.
|
| Return -1 on failure.
|
| hex(...)
| B.hex() -> string
|
| Create a string of hexadecimal numbers from a bytes object.
| Example: b'\xb9\x01\xef'.hex() -> 'b901ef'.
|
| index(...)
| B.index(sub[, start[, end]]) -> int
|
| Return the lowest index in B where subsection sub is found,
| such that sub is contained within B[start,end]. Optional
| arguments start and end are interpreted as in slice notation.
|
| Raises ValueError when the subsection is not found.
|
| isalnum(...)
| B.isalnum() -> bool
|
| Return True if all characters in B are alphanumeric
| and there is at least one character in B, False otherwise.
|
| isalpha(...)
| B.isalpha() -> bool
|
| Return True if all characters in B are alphabetic
| and there is at least one character in B, False otherwise.
|
| isascii(...)
| B.isascii() -> bool
|
| Return True if B is empty or all characters in B are ASCII,
| False otherwise.
|
| isdigit(...)
| B.isdigit() -> bool
|
| Return True if all characters in B are digits
| and there is at least one character in B, False otherwise.
|
| islower(...)
| B.islower() -> bool
|
| Return True if all cased characters in B are lowercase and there is
| at least one cased character in B, False otherwise.
|
| isspace(...)
| B.isspace() -> bool
|
| Return True if all characters in B are whitespace
| and there is at least one character in B, False otherwise.
|
| istitle(...)
| B.istitle() -> bool
|
| Return True if B is a titlecased string and there is at least one
| character in B, i.e. uppercase characters may only follow uncased
| characters and lowercase characters only cased ones. Return False
| otherwise.
|
| isupper(...)
| B.isupper() -> bool
|
| Return True if all cased characters in B are uppercase and there is
| at least one cased character in B, False otherwise.
|
| join(self, iterable_of_bytes, /)
| Concatenate any number of bytes objects.
|
| The bytes whose method is called is inserted in between each pair.
|
| The result is returned as a new bytes object.
|
| Example: b'.'.join([b'ab', b'pq', b'rs']) -> b'ab.pq.rs'.
|
| ljust(...)
| B.ljust(width[, fillchar]) -> copy of B
|
| Return B left justified in a string of length width. Padding is
| done using the specified fill character (default is a space).
|
| lower(...)
| B.lower() -> copy of B
|
| Return a copy of B with all ASCII characters converted to lowercase.
|
| lstrip(self, bytes=None, /)
| Strip leading bytes contained in the argument.
|
| If the argument is omitted or None, strip leading ASCII whitespace.
|
| partition(self, sep, /)
| Partition the bytes into three parts using the given separator.
|
| This will search for the separator sep in the bytes. If the separator is found,
| returns a 3-tuple containing the part before the separator, the separator
| itself, and the part after it.
|
| If the separator is not found, returns a 3-tuple containing the original bytes
| object and two empty bytes objects.
|
| replace(self, old, new, count=-1, /)
| Return a copy with all occurrences of substring old replaced by new.
|
| count
| Maximum number of occurrences to replace.
| -1 (the default value) means replace all occurrences.
|
| If the optional argument count is given, only the first count occurrences are
| replaced.
|
| rfind(...)
| B.rfind(sub[, start[, end]]) -> int
|
| Return the highest index in B where subsection sub is found,
| such that sub is contained within B[start,end]. Optional
| arguments start and end are interpreted as in slice notation.
|
| Return -1 on failure.
|
| rindex(...)
| B.rindex(sub[, start[, end]]) -> int
|
| Return the highest index in B where subsection sub is found,
| such that sub is contained within B[start,end]. Optional
| arguments start and end are interpreted as in slice notation.
|
| Raise ValueError when the subsection is not found.
|
| rjust(...)
| B.rjust(width[, fillchar]) -> copy of B
|
| Return B right justified in a string of length width. Padding is
| done using the specified fill character (default is a space)
|
| rpartition(self, sep, /)
| Partition the bytes into three parts using the given separator.
|
| This will search for the separator sep in the bytes, starting at the end. If
| the separator is found, returns a 3-tuple containing the part before the
| separator, the separator itself, and the part after it.
|
| If the separator is not found, returns a 3-tuple containing two empty bytes
| objects and the original bytes object.
|
| rsplit(self, /, sep=None, maxsplit=-1)
| Return a list of the sections in the bytes, using sep as the delimiter.
|
| sep
| The delimiter according which to split the bytes.
| None (the default value) means split on ASCII whitespace characters
| (space, tab, return, newline, formfeed, vertical tab).
| maxsplit
| Maximum number of splits to do.
| -1 (the default value) means no limit.
|
| Splitting is done starting at the end of the bytes and working to the front.
|
| rstrip(self, bytes=None, /)
| Strip trailing bytes contained in the argument.
|
| If the argument is omitted or None, strip trailing ASCII whitespace.
|
| split(self, /, sep=None, maxsplit=-1)
| Return a list of the sections in the bytes, using sep as the delimiter.
|
| sep
| The delimiter according which to split the bytes.
| None (the default value) means split on ASCII whitespace characters
| (space, tab, return, newline, formfeed, vertical tab).
| maxsplit
| Maximum number of splits to do.
| -1 (the default value) means no limit.
|
| splitlines(self, /, keepends=False)
| Return a list of the lines in the bytes, breaking at line boundaries.
|
| Line breaks are not included in the resulting list unless keepends is given and
| true.
|
| startswith(...)
| B.startswith(prefix[, start[, end]]) -> bool
|
| Return True if B starts with the specified prefix, False otherwise.
| With optional start, test B beginning at that position.
| With optional end, stop comparing B at that position.
| prefix can also be a tuple of bytes to try.
|
| strip(self, bytes=None, /)
| Strip leading and trailing bytes contained in the argument.
|
| If the argument is omitted or None, strip leading and trailing ASCII whitespace.
|
| swapcase(...)
| B.swapcase() -> copy of B
|
| Return a copy of B with uppercase ASCII characters converted
| to lowercase ASCII and vice versa.
|
| title(...)
| B.title() -> copy of B
|
| Return a titlecased version of B, i.e. ASCII words start with uppercase
| characters, all remaining cased characters have lowercase.
|
| translate(self, table, /, delete=b'')
| Return a copy with each character mapped by the given translation table.
|
| table
| Translation table, which must be a bytes object of length 256.
|
| All characters occurring in the optional argument delete are removed.
| The remaining characters are mapped through the given translation table.
|
| upper(...)
| B.upper() -> copy of B
|
| Return a copy of B with all ASCII characters converted to uppercase.
|
| zfill(...)
| B.zfill(width) -> copy of B
|
| Pad a numeric string B with zeros on the left, to fill a field
| of the specified width. B is never truncated.
|
| ----------------------------------------------------------------------
| Class methods defined here:
|
| fromhex(string, /) from builtins.type
| Create a bytes object from a string of hexadecimal numbers.
|
| Spaces between two numbers are accepted.
| Example: bytes.fromhex('B9 01EF') -> b'\\xb9\\x01\\xef'.
|
| ----------------------------------------------------------------------
| Static methods defined here:
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| maketrans(frm, to, /)
| Return a translation table useable for the bytes or bytearray translate method.
|
| The returned table will be one where each byte in frm is mapped to the byte at
| the same position in to.
|
| The bytes objects frm and to must be of the same length.
返回一个新的二进制序列 bytes 对象。参数可以是：
- 0~255 的整数组成的可迭代类型
- 字符串，并指定编码格式 encoding
- 与缓冲区接口一致的对象
- 整数
- 或者不传参数
type(bytes)
type
bytes([1,2,3])
b'\x01\x02\x03'
bytes('嗨', 'utf-8')
b'\xe5\x97\xa8'
bytes(3)
b'\x00\x00\x00'
bytes()
b''
