Python generators are a type of iterator in Python, with the important caviat that you can only iterate over them once.
They are created by writing a function what uses the keyword
yield rather than
Generators can be annotated with the
Generator type that is defined in the
Generator[yield_type, send_type, return_type]
The following code example chunks up a list:
def chunkify(l: List[Any], n: int) -> Generator[List[Any], None, None]: """ Provides a generator which provides chunks of size n of the list. Args: l: The list to chunk up. n: The number of list elements to include in each chunk. Each chunk will be of length n, except for the last chunk, which may be from 1 to length n depending on the number of remaining elements. Returns: A generator which, when iterated over, provides the chunks. """ for i in range(0, len(l), n): # Make sure we don't go over the bounds of the iterable on the last chunk upper_bound = min(i + n, len(l)) yield l[i : upper_bound]
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