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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 clear(self):
 """Clear the contents of the data structure"""

        self.title = None
        self.numbers = np.zeros(0, int)
        self.atom_types = [] # the atom_types in the second column, used to associate ff parameters
        self.charges = [] # ff charges
        self.names = [] # a name that is unique for the molecule composition and connectivity
        self.molecules = np.zeros(0, int) # a counter for each molecule
        self.bonds = np.zeros((0, 2), int)
        self.bends = np.zeros((0, 3), int)
        self.dihedrals = np.zeros((0, 4), int)
        self.impropers = np.zeros((0, 4), int)

        self.name_cache = {}