How to use the oauthlib.oauth1.rfc5849.utils.escape function in oauthlib

text = base_string

    # key is set to the concatenated values of:
    # 1.  The client shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    key = utils.escape(client_secret or '')

    # 2.  An "&" character (ASCII code 38), which MUST be included
    #     even when either secret is empty.
    key += '&'

    # 3.  The token shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    key += utils.escape(resource_owner_secret or '')

    # FIXME: HMAC does not support unicode!
    key_utf8 = key.encode('utf-8')
    text_utf8 = text.encode('utf-8')
    signature = hmac.new(key_utf8, text_utf8, hashlib.sha256)

    # digest  is used to set the value of the "oauth_signature" protocol
    #         parameter, after the result octet string is base64-encoded
    #         per `RFC2045, Section 6.8`.
    #
    # .. _`RFC2045, Section 6.8`: https://tools.ietf.org/html/rfc2045#section-6.8
    return binascii.b2a_base64(signature.digest())[:-1].decode('utf-8')

key%3D9djdj82h48djs9d2%26oauth_nonce%3D7d8f3e4a%26oauth_signature_m
        ethod%3DHMAC-SHA1%26oauth_timestamp%3D137131201%26oauth_token%3Dkkk
        9d7dh3k39sjv7

    .. _`section 3.4.1.1`: https://tools.ietf.org/html/rfc5849#section-3.4.1.1
    """

    # The signature base string is constructed by concatenating together,
    # in order, the following HTTP request elements:

    # 1.  The HTTP request method in uppercase.  For example: "HEAD",
    #     "GET", "POST", etc.  If the request uses a custom HTTP method, it
    #     MUST be encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    base_string = utils.escape(http_method.upper())

    # 2.  An "&" character (ASCII code 38).
    base_string += '&'

    # 3.  The base string URI from `Section 3.4.1.2`_, after being encoded
    #     (`Section 3.6`_).
    #
    # .. _`Section 3.4.1.2`: https://tools.ietf.org/html/rfc5849#section-3.4.1.2
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    base_string += utils.escape(base_str_uri)

    # 4.  An "&" character (ASCII code 38).
    base_string += '&'

    # 5.  The request parameters as normalized in `Section 3.4.1.3.2`_, after
    #     being encoded (`Section 3.6`).

.. _`section 3.5.1`: https://tools.ietf.org/html/rfc5849#section-3.5.1
    .. _`RFC2617`: https://tools.ietf.org/html/rfc2617
    """
    headers = headers or {}

    # Protocol parameters SHALL be included in the "Authorization" header
    # field as follows:
    authorization_header_parameters_parts = []
    for oauth_parameter_name, value in oauth_params:
        # 1.  Parameter names and values are encoded per Parameter Encoding
        #     (`Section 3.6`_)
        #
        # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
        escaped_name = utils.escape(oauth_parameter_name)
        escaped_value = utils.escape(value)

        # 2.  Each parameter's name is immediately followed by an "=" character
        #     (ASCII code 61), a """ character (ASCII code 34), the parameter
        #     value (MAY be empty), and another """ character (ASCII code 34).
        part = '{0}="{1}"'.format(escaped_name, escaped_value)

        authorization_header_parameters_parts.append(part)

    # 3.  Parameters are separated by a "," character (ASCII code 44) and
    #     OPTIONAL linear whitespace per `RFC2617`_.
    #
    # .. _`RFC2617`: https://tools.ietf.org/html/rfc2617
    authorization_header_parameters = ', '.join(
        authorization_header_parameters_parts)

dj82h48djs9d2&oauth_nonce=7d8f3e4a&oauth_signature_method=HMAC-SHA1
        &oauth_timestamp=137131201&oauth_token=kkk9d7dh3k39sjv7

    .. _`section 3.4.1.3.2`: https://tools.ietf.org/html/rfc5849#section-3.4.1.3.2
    """

    # The parameters collected in `Section 3.4.1.3`_ are normalized into a
    # single string as follows:
    #
    # .. _`Section 3.4.1.3`: https://tools.ietf.org/html/rfc5849#section-3.4.1.3

    # 1.  First, the name and value of each parameter are encoded
    #     (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    key_values = [(utils.escape(k), utils.escape(v)) for k, v in params]

    # 2.  The parameters are sorted by name, using ascending byte value
    #     ordering.  If two or more parameters share the same name, they
    #     are sorted by their value.
    key_values.sort()

    # 3.  The name of each parameter is concatenated to its corresponding
    #     value using an "=" character (ASCII code 61) as a separator, even
    #     if the value is empty.
    parameter_parts = ['{0}={1}'.format(k, v) for k, v in key_values]

    # 4.  The sorted name/value pairs are concatenated together into a
    #     single string by using an "&" character (ASCII code 38) as
    #     separator.
    return '&'.join(parameter_parts)

.. _`section 3.4.2`: http://tools.ietf.org/html/rfc5849#section-3.4.2
    """

    # The HMAC-SHA1 function variables are used in following way:

    # text is set to the value of the signature base string from
    # `Section 3.4.1.1`_.
    #
    # .. _`Section 3.4.1.1`: http://tools.ietf.org/html/rfc5849#section-3.4.1.1
    text = base_string

    # key is set to the concatenated values of:
    # 1.  The client shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: http://tools.ietf.org/html/rfc5849#section-3.6
    key = utils.escape(client_secret or '')

    # 2.  An "&" character (ASCII code 38), which MUST be included
    #     even when either secret is empty.
    key += '&'

    # 3.  The token shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: http://tools.ietf.org/html/rfc5849#section-3.6
    key += utils.escape(resource_owner_secret or '')

    # FIXME: HMAC does not support unicode!
    key_utf8 = key.encode('utf-8')
    text_utf8 = text.encode('utf-8')
    signature = hmac.new(key_utf8, text_utf8, hashlib.sha1)

    # digest  is used to set the value of the "oauth_signature" protocol

dj82h48djs9d2&oauth_nonce=7d8f3e4a&oauth_signature_method=HMAC-SHA1
        &oauth_timestamp=137131201&oauth_token=kkk9d7dh3k39sjv7

    .. _`section 3.4.1.3.2`: http://tools.ietf.org/html/rfc5849#section-3.4.1.3.2
    """

    # The parameters collected in `Section 3.4.1.3`_ are normalized into a
    # single string as follows:
    #
    # .. _`Section 3.4.1.3`: http://tools.ietf.org/html/rfc5849#section-3.4.1.3

    # 1.  First, the name and value of each parameter are encoded
    #     (`Section 3.6`_).
    #
    # .. _`Section 3.6`: http://tools.ietf.org/html/rfc5849#section-3.6
    key_values = [(utils.escape(k), utils.escape(v)) for k, v in params]

    # 2.  The parameters are sorted by name, using ascending byte value
    #     ordering.  If two or more parameters share the same name, they
    #     are sorted by their value.
    key_values.sort()

    # 3.  The name of each parameter is concatenated to its corresponding
    #     value using an "=" character (ASCII code 61) as a separator, even
    #     if the value is empty.
    parameter_parts = ['{0}={1}'.format(k, v) for k, v in key_values]

    # 4.  The sorted name/value pairs are concatenated together into a
    #     single string by using an "&" character (ASCII code 38) as
    #     separator.
    return '&'.join(parameter_parts)

# 1.  The HTTP request method in uppercase.  For example: "HEAD",
    #     "GET", "POST", etc.  If the request uses a custom HTTP method, it
    #     MUST be encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    base_string = utils.escape(http_method.upper())

    # 2.  An "&" character (ASCII code 38).
    base_string += '&'

    # 3.  The base string URI from `Section 3.4.1.2`_, after being encoded
    #     (`Section 3.6`_).
    #
    # .. _`Section 3.4.1.2`: https://tools.ietf.org/html/rfc5849#section-3.4.1.2
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    base_string += utils.escape(base_str_uri)

    # 4.  An "&" character (ASCII code 38).
    base_string += '&'

    # 5.  The request parameters as normalized in `Section 3.4.1.3.2`_, after
    #     being encoded (`Section 3.6`).
    #
    # .. _`Section 3.4.1.3.2`: https://tools.ietf.org/html/rfc5849#section-3.4.1.3.2
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    base_string += utils.escape(normalized_encoded_request_parameters)

    return base_string

# 1.  The HTTP request method in uppercase.  For example: "HEAD",
    #     "GET", "POST", etc.  If the request uses a custom HTTP method, it
    #     MUST be encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: http://tools.ietf.org/html/rfc5849#section-3.6
    base_string = utils.escape(http_method.upper())

    # 2.  An "&" character (ASCII code 38).
    base_string += '&'

    # 3.  The base string URI from `Section 3.4.1.2`_, after being encoded
    #     (`Section 3.6`_).
    #
    # .. _`Section 3.4.1.2`: http://tools.ietf.org/html/rfc5849#section-3.4.1.2
    # .. _`Section 3.4.6`: http://tools.ietf.org/html/rfc5849#section-3.4.6
    base_string += utils.escape(base_string_uri)

    # 4.  An "&" character (ASCII code 38).
    base_string += '&'

    # 5.  The request parameters as normalized in `Section 3.4.1.3.2`_, after
    #     being encoded (`Section 3.6`).
    #
    # .. _`Section 3.4.1.3.2`: http://tools.ietf.org/html/rfc5849#section-3.4.1.3.2
    # .. _`Section 3.4.6`: http://tools.ietf.org/html/rfc5849#section-3.4.6
    base_string += utils.escape(normalized_encoded_request_parameters)

    return base_string

.. _`section 3.4.2`: https://tools.ietf.org/html/rfc5849#section-3.4.2
    """

    # The HMAC-SHA1 function variables are used in following way:

    # text is set to the value of the signature base string from
    # `Section 3.4.1.1`_.
    #
    # .. _`Section 3.4.1.1`: https://tools.ietf.org/html/rfc5849#section-3.4.1.1
    text = base_string

    # key is set to the concatenated values of:
    # 1.  The client shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    key = utils.escape(client_secret or '')

    # 2.  An "&" character (ASCII code 38), which MUST be included
    #     even when either secret is empty.
    key += '&'

    # 3.  The token shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    key += utils.escape(resource_owner_secret or '')

    # FIXME: HMAC does not support unicode!
    key_utf8 = key.encode('utf-8')
    text_utf8 = text.encode('utf-8')
    signature = hmac.new(key_utf8, text_utf8, hashlib.sha1)

    # digest  is used to set the value of the "oauth_signature" protocol