By comparing the return value of type with any type, you can check whether the object is of that type. If you want to check if it is one of several types, use in and multiple types of tuples. It is also possible to define functions that change the processing depending on the argument type.
If the separator is not found, return a 3-tuple containing two empty strings, followed by the string itself. Return a list of the words in the string, using sep as the delimiter string.
If maxsplit is given, at most maxsplit splits are done, the rightmost ones. If sep is not specified or None , any whitespace string is a separator. Except for splitting from the right, rsplit behaves like split which is described in detail below.
Return a copy of the string with trailing characters removed. The chars argument is not a suffix; rather, all combinations of its values are stripped:. If maxsplit is not specified or -1 , then there is no limit on the number of splits all possible splits are made. If sep is given, consecutive delimiters are not grouped together and are deemed to delimit empty strings for example, '1,,2'. Splitting an empty string with a specified separator returns ['']. If sep is not specified or is None , a different splitting algorithm is applied: runs of consecutive whitespace are regarded as a single separator, and the result will contain no empty strings at the start or end if the string has leading or trailing whitespace.
Consequently, splitting an empty string or a string consisting of just whitespace with a None separator returns []. Return a list of the lines in the string, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true. This method splits on the following line boundaries. In particular, the boundaries are a superset of universal newlines.
Unlike split when a delimiter string sep is given, this method returns an empty list for the empty string, and a terminal line break does not result in an extra line:. Return True if string starts with the prefix , otherwise return False. With optional start , test string beginning at that position. With optional end , stop comparing string at that position. Return a copy of the string with the leading and trailing characters removed.
The chars argument is not a prefix or suffix; rather, all combinations of its values are stripped:. The outermost leading and trailing chars argument values are stripped from the string. Characters are removed from the leading end until reaching a string character that is not contained in the set of characters in chars. A similar action takes place on the trailing end. Return a copy of the string with uppercase characters converted to lowercase and vice versa. Note that it is not necessarily true that s.
Return a titlecased version of the string where words start with an uppercase character and the remaining characters are lowercase. The algorithm uses a simple language-independent definition of a word as groups of consecutive letters. The definition works in many contexts but it means that apostrophes in contractions and possessives form word boundaries, which may not be the desired result:. Return a copy of the string in which each character has been mapped through the given translation table.
When indexed by a Unicode ordinal an integer , the table object can do any of the following: return a Unicode ordinal or a string, to map the character to one or more other characters; return None , to delete the character from the return string; or raise a LookupError exception, to map the character to itself.
You can use str. See also the codecs module for a more flexible approach to custom character mappings. Return a copy of the string with all the cased characters 4 converted to uppercase.
Note that s. The formatting operations described here exhibit a variety of quirks that lead to a number of common errors such as failing to display tuples and dictionaries correctly. Using the newer formatted string literals , the str.
This is also known as the string formatting or interpolation operator. The effect is similar to using the sprintf in the C language. If format requires a single argument, values may be a single non-tuple object. A conversion specifier contains two or more characters and has the following components, which must occur in this order:. Mapping key optional , consisting of a parenthesised sequence of characters for example, somename.
Minimum field width optional. Precision optional , given as a '. The mapping key selects the value to be formatted from the mapping. The converted value is left adjusted overrides the '0' conversion if both are given. A length modifier h , l , or L may be present, but is ignored as it is not necessary for Python — so e. Obsolete type — it is identical to 'd'. Floating point format. Uses lowercase exponential format if exponent is less than -4 or not less than precision, decimal format otherwise.
Uses uppercase exponential format if exponent is less than -4 or not less than precision, decimal format otherwise. String converts any Python object using repr. String converts any Python object using str. String converts any Python object using ascii.
The alternate form causes a leading octal specifier '0o' to be inserted before the first digit. The alternate form causes a leading '0x' or '0X' depending on whether the 'x' or 'X' format was used to be inserted before the first digit. The alternate form causes the result to always contain a decimal point, even if no digits follow it. The alternate form causes the result to always contain a decimal point, and trailing zeroes are not removed as they would otherwise be.
The precision determines the number of significant digits before and after the decimal point and defaults to 6. If precision is N , the output is truncated to N characters.
See PEP The core built-in types for manipulating binary data are bytes and bytearray. They are supported by memoryview which uses the buffer protocol to access the memory of other binary objects without needing to make a copy. The array module supports efficient storage of basic data types like bit integers and IEEE double-precision floating values.
Bytes objects are immutable sequences of single bytes. Since many major binary protocols are based on the ASCII text encoding, bytes objects offer several methods that are only valid when working with ASCII compatible data and are closely related to string objects in a variety of other ways.
Firstly, the syntax for bytes literals is largely the same as that for string literals, except that a b prefix is added:. Single quotes: b'still allows embedded "double" quotes'. Double quotes: b"still allows embedded 'single' quotes".
Triple quoted: b'''3 single quotes''' , b"""3 double quotes""". Only ASCII characters are permitted in bytes literals regardless of the declared source code encoding. Any binary values over must be entered into bytes literals using the appropriate escape sequence.
As with string literals, bytes literals may also use a r prefix to disable processing of escape sequences. See String and Bytes literals for more about the various forms of bytes literal, including supported escape sequences.
This is done deliberately to emphasise that while many binary formats include ASCII based elements and can be usefully manipulated with some text-oriented algorithms, this is not generally the case for arbitrary binary data blindly applying text processing algorithms to binary data formats that are not ASCII compatible will usually lead to data corruption.
A zero-filled bytes object of a specified length: bytes From an iterable of integers: bytes range Copying existing binary data via the buffer protocol: bytes obj. Also see the bytes built-in. Since 2 hexadecimal digits correspond precisely to a single byte, hexadecimal numbers are a commonly used format for describing binary data. Accordingly, the bytes type has an additional class method to read data in that format:.
This bytes class method returns a bytes object, decoding the given string object. A reverse conversion function exists to transform a bytes object into its hexadecimal representation. If you want to make the hex string easier to read, you can specify a single character separator sep parameter to include in the output.
By default between each byte. Positive values calculate the separator position from the right, negative values from the left. Since bytes objects are sequences of integers akin to a tuple , for a bytes object b , b[0] will be an integer, while b[] will be a bytes object of length 1.
This contrasts with text strings, where both indexing and slicing will produce a string of length 1. The representation of bytes objects uses the literal format b' You can always convert a bytes object into a list of integers using list b. For Python 2.
This was a backwards compatibility workaround to account for the fact that Python originally only supported 8-bit text, and Unicode text was a later addition. In Python 3. There is no dedicated literal syntax for bytearray objects, instead they are always created by calling the constructor:. Creating an empty instance: bytearray.
Creating a zero-filled instance with a given length: bytearray From an iterable of integers: bytearray range Copying existing binary data via the buffer protocol: bytearray b'Hi! As bytearray objects are mutable, they support the mutable sequence operations in addition to the common bytes and bytearray operations described in Bytes and Bytearray Operations.
Also see the bytearray built-in. Accordingly, the bytearray type has an additional class method to read data in that format:. This bytearray class method returns bytearray object, decoding the given string object. A reverse conversion function exists to transform a bytearray object into its hexadecimal representation. Since bytearray objects are sequences of integers akin to a list , for a bytearray object b , b[0] will be an integer, while b[] will be a bytearray object of length 1.
The representation of bytearray objects uses the bytes literal format bytearray b' You can always convert a bytearray object into a list of integers using list b. Both bytes and bytearray objects support the common sequence operations. They interoperate not just with operands of the same type, but with any bytes-like object. Due to this flexibility, they can be freely mixed in operations without causing errors.
However, the return type of the result may depend on the order of operands. For example, you have to write:. Some bytes and bytearray operations assume the use of ASCII compatible binary formats, and hence should be avoided when working with arbitrary binary data. These restrictions are covered below. Return the number of non-overlapping occurrences of subsequence sub in the range [ start , end ]. The subsequence to search for may be any bytes-like object or an integer in the range 0 to If the binary data starts with the prefix string, return bytes[len prefix :].
Otherwise, return a copy of the original binary data:. The prefix may be any bytes-like object. The bytearray version of this method does not operate in place - it always produces a new object, even if no changes were made. If the binary data ends with the suffix string and that suffix is not empty, return bytes[:-len suffix ]. The suffix may be any bytes-like object. Return a string decoded from the given bytes. Other possible values are 'ignore' , 'replace' and any other name registered via codecs.
By default, the errors argument is not checked for best performances, but only used at the first decoding error. Passing the encoding argument to str allows decoding any bytes-like object directly, without needing to make a temporary bytes or bytearray object. Return True if the binary data ends with the specified suffix , otherwise return False. The suffix es to search for may be any bytes-like object. Return the lowest index in the data where the subsequence sub is found, such that sub is contained in the slice s[start:end].
Like find , but raise ValueError when the subsequence is not found. Return a bytes or bytearray object which is the concatenation of the binary data sequences in iterable. A TypeError will be raised if there are any values in iterable that are not bytes-like objects , including str objects.
The separator between elements is the contents of the bytes or bytearray object providing this method. This static method returns a translation table usable for bytes. Split the sequence at the first occurrence of sep , and return a 3-tuple containing the part before the separator, the separator itself or its bytearray copy, and the part after the separator.
If the separator is not found, return a 3-tuple containing a copy of the original sequence, followed by two empty bytes or bytearray objects. The separator to search for may be any bytes-like object. Return a copy of the sequence with all occurrences of subsequence old replaced by new. The subsequence to search for and its replacement may be any bytes-like object. Return the highest index in the sequence where the subsequence sub is found, such that sub is contained within s[start:end].
Like rfind but raises ValueError when the subsequence sub is not found. Split the sequence at the last occurrence of sep , and return a 3-tuple containing the part before the separator, the separator itself or its bytearray copy, and the part after the separator. If the separator is not found, return a 3-tuple containing two empty bytes or bytearray objects, followed by a copy of the original sequence. Return True if the binary data starts with the specified prefix , otherwise return False.
The prefix es to search for may be any bytes-like object. Return a copy of the bytes or bytearray object where all bytes occurring in the optional argument delete are removed, and the remaining bytes have been mapped through the given translation table, which must be a bytes object of length You can use the bytes. Set the table argument to None for translations that only delete characters:. The following methods on bytes and bytearray objects have default behaviours that assume the use of ASCII compatible binary formats, but can still be used with arbitrary binary data by passing appropriate arguments.
Note that all of the bytearray methods in this section do not operate in place, and instead produce new objects. Return a copy of the object centered in a sequence of length width. For bytes objects, the original sequence is returned if width is less than or equal to len s.
Return a copy of the object left justified in a sequence of length width. Return a copy of the sequence with specified leading bytes removed. The chars argument is a binary sequence specifying the set of byte values to be removed - the name refers to the fact this method is usually used with ASCII characters.
The binary sequence of byte values to remove may be any bytes-like object. See removeprefix for a method that will remove a single prefix string rather than all of a set of characters.
Return a copy of the object right justified in a sequence of length width. Split the binary sequence into subsequences of the same type, using sep as the delimiter string. Return a copy of the sequence with specified trailing bytes removed. See removesuffix for a method that will remove a single suffix string rather than all of a set of characters. If maxsplit is not specified or is -1 , then there is no limit on the number of splits all possible splits are made.
If sep is given, consecutive delimiters are not grouped together and are deemed to delimit empty subsequences for example, b'1,,2'. Splitting an empty sequence with a specified separator returns [b''] or [bytearray b'' ] depending on the type of object being split.
The sep argument may be any bytes-like object. If sep is not specified or is None , a different splitting algorithm is applied: runs of consecutive ASCII whitespace are regarded as a single separator, and the result will contain no empty strings at the start or end if the sequence has leading or trailing whitespace.
Consequently, splitting an empty sequence or a sequence consisting solely of ASCII whitespace without a specified separator returns []. Return a copy of the sequence with specified leading and trailing bytes removed.
The following methods on bytes and bytearray objects assume the use of ASCII compatible binary formats and should not be applied to arbitrary binary data.
Return a copy of the sequence with each byte interpreted as an ASCII character, and the first byte capitalized and the rest lowercased. Tab positions occur every tabsize bytes default is 8, giving tab positions at columns 0, 8, 16 and so on. To expand the sequence, the current column is set to zero and the sequence is examined byte by byte. Any other byte value is copied unchanged and the current column is incremented by one regardless of how the byte value is represented when printed:.
ASCII decimal digits are those byte values in the sequence b''. See bytes. Return a copy of the sequence with all the uppercase ASCII characters converted to their corresponding lowercase counterpart.
This method uses the universal newlines approach to splitting lines. Return a copy of the sequence with all the lowercase ASCII characters converted to their corresponding uppercase counterpart and vice-versa.
Unlike str. Return a titlecased version of the binary sequence where words start with an uppercase ASCII character and the remaining characters are lowercase. Uncased byte values are left unmodified. All other byte values are uncased. Return a copy of the sequence with all the lowercase ASCII characters converted to their corresponding uppercase counterpart. For bytes objects, the original sequence is returned if width is less than or equal to len seq.
If the value being printed may be a tuple or dictionary, wrap it in a tuple. This is also known as the bytes formatting or interpolation operator. Bytes converts any Python object using repr obj. Create a memoryview that references object. Built-in objects that support the buffer protocol include bytes and bytearray. A memoryview has the notion of an element , which is the atomic memory unit handled by the originating object.
For many simple types such as bytes and bytearray , an element is a single byte, but other types such as array. If view. For higher dimensions, the length is equal to the length of the nested list representation of the view. The itemsize attribute will give you the number of bytes in a single element. A memoryview supports slicing and indexing to expose its data. One-dimensional slicing will result in a subview:. If format is one of the native format specifiers from the struct module, indexing with an integer or a tuple of integers is also supported and returns a single element with the correct type.
One-dimensional memoryviews can be indexed with an integer or a one-integer tuple. Multi-dimensional memoryviews can be indexed with tuples of exactly ndim integers where ndim is the number of dimensions.
Zero-dimensional memoryviews can be indexed with the empty tuple. If the underlying object is writable, the memoryview supports one-dimensional slice assignment. Resizing is not allowed:. For the subset of struct format strings currently supported by tolist , v and w are equal if v.
If either format string is not supported by the struct module, then the objects will always compare as unequal even if the format strings and buffer contents are identical :. Return the data in the buffer as a bytestring. This is equivalent to calling the bytes constructor on the memoryview. Class of type tuple. Creating object of each class.
Will print accordingly whether both. Python3 program to demonstrate. New class has no base class with the.
Print type which returns class 'type'. Dynamically initialize Newer class. It will derive from the base class test. Next type and isinstance in Python. Recommended Articles. Print the Fibonacci sequence. Check leap year. Reference Materials Built-in Functions. List Methods. Dictionary Methods.
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