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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 get_requirements(lookup=None):
    '''get_requirements reads in requirements and versions from
    the lookup obtained with get_lookup'''

    if lookup == None:
        lookup = get_lookup()

    install_requires = []
    for module in lookup['INSTALL_REQUIRES']:
        module_name = module[0]
        module_meta = module[1]
        if "exact_version" in module_meta:
            dependency = "%s==%s" %(module_name,module_meta['exact_version'])
        elif "min_version" in module_meta:
            if module_meta['min_version'] == None:
                dependency = module_name
            else:
                dependency = "%s>=%s" %(module_name,module_meta['min_version'])
        install_requires.append(dependency)
    return install_requires