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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _oauth10a_signature( consumer_token: Dict[str, Any], method: str, url: str, parameters: Dict[str, Any] = {}, token: Dict[str, Any] = None, ) -> bytes: """Calculates the HMAC-SHA1 OAuth 1.0a signature for the given request. See http://oauth.net/core/1.0a/#signing_process """

    parts = urllib.parse.urlparse(url)
    scheme, netloc, path = parts[:3]
    normalized_url = scheme.lower() + "://" + netloc.lower() + path

    base_elems = []
    base_elems.append(method.upper())
    base_elems.append(normalized_url)
    base_elems.append(
        "&".join(
            "%s=%s" % (k, _oauth_escape(str(v))) for k, v in sorted(parameters.items())
        )
    )

    base_string = "&".join(_oauth_escape(e) for e in base_elems)
    key_elems = [escape.utf8(urllib.parse.quote(consumer_token["secret"], safe="~"))]
    key_elems.append(
        escape.utf8(urllib.parse.quote(token["secret"], safe="~") if token else "")
    )
    key = b"&".join(key_elems)

    hash = hmac.new(key, escape.utf8(base_string), hashlib.sha1)
    return binascii.b2a_base64(hash.digest())[:-1]