code: def validate_signature(self, signature, data, encoding='utf8'):
          
  
          if isinstance(data, string_types):
              data = bytearray(data, encoding)
          if isinstance(signature, string_types):
              signature = bytearray(signature, encoding)
  
          secret_key = bytearray(self.secret_key, 'utf8')
          hashed = hmac.new(secret_key, data, sha1)
          encoded = b64encode(hashed.digest())
  
          return encoded.strip() == signature.strip()
docs: Validate the signature for the provided data.
  
          Args:
              signature (str or bytes or bytearray): Signature that was provided
                  for the request.
              data (str or bytes or bytearray): Data string to validate against
                  the signature.
              encoding (str, optional): If a string was provided for ``data`` or
                  ``signature``, this is the character encoding.
  
          Returns:
              bool: Whether the signature is valid for the provided data.