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#!/usr/bin/env python
"""A more advanced Mapper, using Python iterators and generators."""

import sys

def read_input(file):
    for line in file:
        # split the line into words
        yield line.split()

def main(separator='\t'):
    # input comes from STDIN (standard input)
    data = read_input(sys.stdin)
    for words in data:
        # write the results to STDOUT (standard output);
        # what we output here will be the input for the
        # Reduce step, i.e. the input for reducer.py
        #
        # tab-delimited; the trivial word count is 1
        for word in words:
            print '%s%s%d' % (word, separator, 1)

if __name__ == "__main__":
    main()

class DemoModel(models.Model):
    demoid = models.UUIDField(primary_key=True, default=uuid.uuid1)
    str_field = models.CharField(max_length=100)

>>> from app1.models import DemoModel
>>> m = DemoModel.objects.create(**{'str_field': 1})
>>> type(m.str_field)       ## 这时候字段类型是int而不是预想中的str
<class 'int'>
>>> m.str_field
1
>>> m = DemoModel.objects.first()
>>> type(m.str_field)       ## 此时字段类型是str
<class 'str'>
>>> m.str_field
'1'

>>> a = arange(24)
>>> a
array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16,
       17, 18, 19, 20, 21, 22, 23])
>>> b = a.reshape((2, 3, 4))
>>> b
array([[[ 0,  1,  2,  3],
        [ 4,  5,  6,  7],
        [ 8,  9, 10, 11]],

       [[12, 13, 14, 15],
        [16, 17, 18, 19],
        [20, 21, 22, 23]]])
>>> c = b.reshape((3, 8))
>>> c
array([[ 0,  1,  2,  3,  4,  5,  6,  7],
       [ 8,  9, 10, 11, 12, 13, 14, 15],
       [16, 17, 18, 19, 20, 21, 22, 23]])