.. module:: requests.models

Response Headers
----------------

We can view the server's response headers using a Python dictionary::

    >>> r.headers
    {
        'content-encoding': 'gzip',
        'transfer-encoding': 'chunked',
        'connection': 'close',
        'server': 'nginx/1.0.4',
        'x-runtime': '148ms',
        'etag': '"e1ca502697e5c9317743dc078f67693f"',
        'content-type': 'application/json'
    }

The dictionary is special, though: it's made just for HTTP headers. According to
`RFC 7230 <http://tools.ietf.org/html/rfc7230#section-3.2>`_, HTTP Header names
are case-insensitive.

So, we can access the headers using any capitalization we want::

    >>> r.headers['Content-Type']
    'application/json'

    >>> r.headers.get('content-type')
    'application/json'

It is also special in that the server could have sent the same header multiple
times with different values, but requests combines them so they can be
represented in the dictionary within a single mapping, as per
`RFC 7230 <http://tools.ietf.org/html/rfc7230#section-3.2>`_:

    A recipient MAY combine multiple header fields with the same field name
    into one "field-name: field-value" pair, without changing the semantics
    of the message, by appending each subsequent field value to the combined
    field value in order, separated by a comma.