Python iterators and generators

Always thought that Python generator is a list generation, OK, I read less.

In fact, the generator is the generator object that implements the iterator protocol using yield returns. As follows:

Class Data (object):    def __init__ (self, *args):        self._data = list (args)    def __iter__ (self): for        x in Self._data:            yield x    d = data ()    >>> d.__iter__ ()    <generator object __iter__ at 0x7f8556d4cdc8>

Use D.next () in Python2 to return the next value of D,
In Python3, you need to use Dnext() to return the next value of the generator for D, which can be used for the process to be built.

About Iterators
Depending on the iterator protocol, both ITER() and Next () Two methods need to be implemented, which returns an Iterator object, which returns data until the end of the stopiteration exception is thrown.

Class Data (object):d EF __init__ (Self, *args):    self.data = list (args)    Self.index = 0def __iter__ (self):    return selfdef __next__ (self):    if Self.index < Len (self.data):        d =  Self.data[self.index]        Self.index +=1    Else:        raise Stopiteration ()    return D

Python iterators and generators