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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 ctc(target, pore_diameter='pore.diameter'):
 r""" Calculate throat length assuming point-like pores, i.e. center-to-center distance between pores. Also, this models assumes that pores and throat centroids are colinear. Parameters target : OpenPNM Object The object which this model is associated with. This controls the length of the calculated array, and also provides access to other necessary properties. pore_diameter : string Dictionary key of the pore diameter values """

    _np.warnings.filterwarnings('ignore', category=RuntimeWarning)

    network = target.project.network
    throats = network.map_throats(throats=target.Ts, origin=target)
    cn = network['throat.conns'][throats]
    C1 = network['pore.coords'][cn[:, 0]]
    C2 = network['pore.coords'][cn[:, 1]]
    value = _sqrt(((C1 - C2)**2).sum(axis=1))

    _np.warnings.filterwarnings('default', category=RuntimeWarning)

    return value