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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 detect(self, sampfrom=0, sampto='end', learn=True, verbose=True):
 """ Detect qrs locations between two samples. Parameters sampfrom : int, optional The starting sample number to run the detection on. sampto : int, optional The final sample number to run the detection on. Set as 'end' to run on the entire signal. learn : bool, optional Whether to apply learning on the signal before running the main detection. If learning fails or is not conducted, the default configuration parameters will be used to initialize these variables. See the `XQRS._learn_init_params` docstring for details. verbose : bool, optional Whether to display the stages and outcomes of the detection process. """

        if sampfrom < 0:
            raise ValueError("'sampfrom' cannot be negative")
        self.sampfrom = sampfrom

        if sampto == 'end':
            sampto = self.sig_len
        elif sampto > self.sig_len:
            raise ValueError("'sampto' cannot exceed the signal length")
        self.sampto = sampto
        self.verbose = verbose

        # Don't attempt to run on a flat signal
        if np.max(self.sig) == np.min(self.sig):
            self.qrs_inds = np.empty(0)
            if self.verbose:
                print('Flat signal. Detection skipped.')
            return

        # Get/set signal configuration fields from Conf object
        self._set_conf()
        # Bandpass filter the signal
        self._bandpass()
        # Compute moving wave integration of filtered signal
        self._mwi()

        # Initialize the running parameters
        if learn:
            self._learn_init_params()
        else:
            self._set_default_init_params()

        # Run the detection
        self._run_detection()