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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 resname_in_proximity(resname, model, chains, resnums, threshold=5):
 """Search within the proximity of a defined list of residue numbers and their chains for any specifed residue name. Args: resname (str):
 Residue name to search for in proximity of specified chains + resnums model: Biopython Model object chains (str, list):
 Chain ID or IDs to check resnums (int, list):
 Residue numbers within the chain to check threshold (float):
 Cutoff in Angstroms for returning True if a RESNAME is near Returns: bool: True if a RESNAME is within the threshold cutoff """

    residues = [r for r in model.get_residues() if r.get_resname() == resname]

    chains = ssbio.utils.force_list(chains)
    resnums = ssbio.utils.force_list(resnums)

    for chain in chains:
        for resnum in resnums:
            my_residue_last_atom = model[chain][resnum].child_list[-1]
            for rz in residues:
                distance = rz.child_list[-1] - my_residue_last_atom
                if distance < threshold:
                    # print(resnum, rz, distance)
                    return True

    return False