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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 _fix_uncontracted(basis):
    '''
    Forces the contraction coefficient of uncontracted shells to 1.0
    '''

    for el in basis['elements'].values():
        if 'electron_shells' not in el:
            continue

        for sh in el['electron_shells']:
            if len(sh['coefficients']) == 1 and len(sh['coefficients'][0]) == 1:
                sh['coefficients'][0][0] = '1.0000000'

            # Some uncontracted shells don't have a coefficient
            if len(sh['coefficients']) == 0:
                sh['coefficients'].append(['1.0000000'])

    return basis