builtins -- builtin functions and exceptions#

All builtin functions and exceptions are described here. They are also available via builtins module.

Functions and types#

abs()

all()

any()

bin()

|see_cpython| python:bytearray.

|see_cpython| python:bytes.

bytes.decode(encoding='utf-8', errors='strict')

Decode the bytes object to a string using the specified encoding.

MicroPython supports the following encodings:

• 'utf-8' or 'utf8' - UTF-8 encoding (default)
• 'ascii' - ASCII encoding (subset of UTF-8)

The errors parameter controls how decoding errors are handled:

• 'strict' - Raise a UnicodeError on invalid UTF-8 (default)
• 'ignore' - Skip invalid bytes (requires MICROPY_PY_BUILTINS_BYTES_DECODE_ERRORS)
• 'replace' - Replace invalid bytes with U+FFFD '�' (requires MICROPY_PY_BUILTINS_BYTES_DECODE_ERRORS)

[!NOTE] Error handler support depends on build configuration. On constrained systems, only 'strict' mode may be available.

Example:

>>> b'\xc2\xa9 2024'.decode('utf-8')  # © symbol
'© 2024'
>>> b'hello\xffworld'.decode('utf-8', 'ignore')  # Skip invalid bytes
'helloworld'

Raises LookupError if the encoding is not supported, or UnicodeError if the data contains invalid UTF-8 and errors='strict'.

callable()

chr()

classmethod()

compile()

delattr(obj, name)

The argument name should be a string, and this function deletes the named attribute from the object given by obj.

dir()

divmod()

enumerate()

eval()

exec()

filter()

getattr()

globals()

hasattr()

hash()

hex()

id()

input()

from_bytes(bytes, byteorder)

In MicroPython, byteorder parameter must be positional (this is compatible with CPython).

to_bytes(size, byteorder, /, *, signed=False)

In MicroPython, byteorder parameter must be positional (this is compatible with CPython).

isinstance()

issubclass()

iter()

len()

locals()

map()

max()

|see_cpython| python:memoryview.

min()

next()

oct()

open()

ord()

pow()

print()

property()

range()

repr()

reversed()

round()

setattr()

The slice builtin is the type that slice objects have.

sorted()

staticmethod()

str.encode(encoding='utf-8')

Encode the string to bytes using the specified encoding.

MicroPython supports the following encodings:

• 'utf-8' or 'utf8' - UTF-8 encoding (default)
• 'ascii' - ASCII encoding (subset of UTF-8)

Example:

>>> '© 2024'.encode('utf-8')  # Copyright symbol
b'\xc2\xa9 2024'

Raises LookupError if the encoding is not supported.

str.center(width)

Return a centered string of length width. Padding is done using spaces.

When Unicode support is enabled (MICROPY_PY_BUILTINS_STR_UNICODE), this method counts Unicode characters rather than bytes, ensuring proper alignment for multi-byte UTF-8 characters.

Example:

>>> 'café'.center(10)  # é is 2 bytes in UTF-8
'   café   '

sum()

super()

type()

zip()

Exceptions#

AssertionError

AttributeError

Exception

ImportError

IndexError

KeyboardInterrupt

|see_cpython| python:KeyboardInterrupt.

See also in the context of soft_bricking.

KeyError

MemoryError

NameError

NotImplementedError

OSError

RuntimeError

StopIteration

SyntaxError

SystemExit

|see_cpython| python:SystemExit.

On non-embedded ports (i.e. Windows and Unix), an unhandled SystemExit exits the MicroPython process in a similar way to CPython.

On embedded ports, an unhandled SystemExit currently causes a soft_reset of MicroPython.

TypeError

|see_cpython| python:TypeError.

ValueError

ZeroDivisionError