code: def _make_api_call(self, method, url, json_params=None):
          
          if self.verbose is True:
              print "\ncrossbarhttp: Request: %s %s" % (method, url)
  
          if json_params is not None:
              encoded_params = json.dumps(json_params)
              headers = {'Content-Type': 'application/json'}
          else:
              encoded_params = None
              headers = {}
  
          if encoded_params is not None and self.verbose is True:
              print "crossbarhttp: Params: " + encoded_params
  
          if self.key is not None and self.secret is not None and encoded_params is not None:
              signature, nonce, timestamp = self._compute_signature(encoded_params)
              params = urllib.urlencode({
                  "timestamp": timestamp,
                  "seq": str(self.sequence),
                  "nonce": nonce,
                  "signature": signature,
                  "key": self.key
              })
              if self.verbose is True:
                  print "crossbarhttp: Signature Params: " + params
              url += "?" + params
  
          # TODO: I can't figure out what this is.  Guessing it is a number you increment on every call
          self.sequence += 1
  
          try:
              request = urllib2.Request(url, encoded_params, headers)
              request.get_method = lambda: method
              response = urllib2.urlopen(request).read()
              if self.verbose is True:
                  print "crossbarhttp: Response: " + response
  
              return json.loads(response)
  
          except urllib2.HTTPError, e:
              if e.code == 400:
                  raise ClientMissingParams(str(e))
              elif e.code == 401:
                  raise ClientSignatureError(str(e))
              else:
                  raise ClientBadUrl(str(e))
          except urllib2.URLError, e:
              raise ClientBadHost(str(e))
docs: Performs the REST API Call
          :param method: HTTP Method
          :param url:  The URL
          :param json_params: The parameters intended to be JSON serialized
          :return: