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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 minimum_pitch(self):
 """ Returns the minimal pitch between two neighboring nodes of the mesh in each direction. :return: Minimal pitch in each direction. """

        pitch = self.pitch
        minimal_pitch = []

        for p in pitch:
            minimal_pitch.append(min(p))

        return min(minimal_pitch)