.-.-.-.-.-

from __future__ import absolute_import
import codecs

from uuid import uuid4
from io import BytesIO

import six
from six import b
from .fields import RequestField

writer = codecs.lookup('utf-8')[3]

def choose_boundary():
    """
    Our embarrassingly-simple replacement for mimetools.choose_boundary.
    """
    return uuid4().hex

def iter_field_objects(fields):
    """
    Iterate over fields.

Supports list of (k, v) tuples and dicts, and lists of
    :class:`~urllib3.fields.RequestField`.

"""
    if isinstance(fields, dict):
        i = six.iteritems(fields)
    else:
        i = iter(fields)

for field in i:
        if isinstance(field, RequestField):
            yield field
        else:
            yield RequestField.from_tuples(*field)

def iter_fields(fields):
    """
    .. deprecated:: 1.6

Iterate over fields.

The addition of :class:`~urllib3.fields.RequestField` makes this function
    obsolete. Instead, use :func:`iter_field_objects`, which returns
    :class:`~urllib3.fields.RequestField` objects.

Supports list of (k, v) tuples and dicts.
    """
    if isinstance(fields, dict):
        return ((k, v) for k, v in six.iteritems(fields))

return ((k, v) for k, v in fields)

def encode_multipart_formdata(fields, boundary=None):
    """
    Encode a dictionary of ``fields`` using the multipart/form-data MIME format.

:param fields:
        Dictionary of fields or list of (key, :class:`~urllib3.fields.RequestField`).

:param boundary:
        If not specified, then a random boundary will be generated using
        :func:`mimetools.choose_boundary`.
    """
    body = BytesIO()
    if boundary is None:
        boundary = choose_boundary()

for field in iter_field_objects(fields):
        body.write(b('--%s\r\n' % (boundary)))

writer(body).write(field.render_headers())
        data = field.data

if isinstance(data, int):
            data = str(data)  # Backwards compatibility

if isinstance(data, six.text_type):
            writer(body).write(data)
        else:
            body.write(data)

body.write(b'\r\n')

body.write(b('--%s--\r\n' % (boundary)))

content_type = str('multipart/form-data; boundary=%s' % boundary)

return body.getvalue(), content_type

/var/../../usr/src/../lib/python3/dist-packages/urllib3/filepost.py