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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_coord_subset_pbc(subset, superset, atol=1e-8, mask=None):
 """ Tests if all fractional coords in subset are contained in superset. Args: subset, superset: List of fractional coords atol (float or size 3 array):
 Tolerance for matching mask (boolean array):
 Mask of matches that are not allowed. i.e. if mask[1,2] == True, then subset[1] cannot be matched to superset[2] Returns: True if all of subset is in superset. """

    c1 = np.array(subset, dtype=np.float64)
    c2 = np.array(superset, dtype=np.float64)
    if mask is not None:
        m = np.array(mask, dtype=np.int)
    else:
        m = np.zeros((len(subset), len(superset)), dtype=np.int)
    atol = np.zeros(3, dtype=np.float64) + atol
    return cuc.is_coord_subset_pbc(c1, c2, atol, m)