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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 is_regular(self):
 r""" Troubleshoot a given regular graph. """

        warn = False
        msg = 'The given matrix'

        # check symmetry
        if np.abs(self.A - self.A.T).sum() > 0:
            warn = True
            msg = '{} is not symmetric,'.format(msg)

        # check parallel edged
        if self.A.max(axis=None) > 1:
            warn = True
            msg = '{} has parallel edges,'.format(msg)

        # check that d is d-regular
        if np.min(self.d) != np.max(self.d):
            warn = True
            msg = '{} is not d-regular,'.format(msg)

        # check that g doesn't contain any self-loop
        if self.A.diagonal().any():
            warn = True
            msg = '{} has self loop.'.format(msg)

        if warn:
            self.logger.warning('{}.'.format(msg[:-1]))