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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 covalent_bonds(atoms, threshold=1.1):
 """Returns all the covalent bonds in a list of `Atom` pairs. Notes ----- Uses information `element_data`, which can be accessed directly through this module i.e. `isambard.ampal.interactions.element_data`. Parameters atoms : [(`Atom`, `Atom`)] List of pairs of `Atoms`. threshold : float, optional Allows deviation from ideal covalent bond distance to be included. For example, a value of 1.1 would allow interactions up to 10% further from the ideal distance to be included. """

    bonds=[]
    for a, b in atoms:
        bond_distance=(
                element_data[a.element.title()]['atomic radius'] + element_data[
                b.element.title()]['atomic radius']) / 100
        dist=distance(a._vector, b._vector)
        if dist <= bond_distance * threshold:
            bonds.append(CovalentBond(a, b, dist))
    return bonds