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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 _process(self):
 """ Coroutine implementing the key match algorithm. Key strokes are sent into this generator, and it calls the appropriate handlers. """

        buffer = self.key_buffer
        retry = False

        while True:
            if retry:
                retry = False
            else:
                buffer.append((yield))

            # If we have some key presses, check for matches.
            if buffer:
                is_prefix_of_longer_match = self._is_prefix_of_longer_match(buffer)
                matches = self._get_matches(buffer)

                # When eager matches were found, give priority to them and also
                # ignore all the longer matches.
                eager_matches = [m for m in matches if m.eager(self._cli_ref())]

                if eager_matches:
                    matches = eager_matches
                    is_prefix_of_longer_match = False

                # Exact matches found, call handler.
                if not is_prefix_of_longer_match and matches:
                    self._call_handler(matches[-1], key_sequence=buffer[:])
                    del buffer[:]  # Keep reference.

                # No match found.
                elif not is_prefix_of_longer_match and not matches:
                    retry = True
                    found = False

                    # Loop over the input, try longest match first and shift.
                    for i in range(len(buffer), 0, -1):
                        matches = self._get_matches(buffer[:i])
                        if matches:
                            self._call_handler(matches[-1], key_sequence=buffer[:i])
                            del buffer[:i]
                            found = True
                            break

                    if not found:
                        del buffer[:1]