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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 prior_from_config(cp, prior_section='prior'):
 """Loads a prior distribution from the given config file. Parameters cp : pycbc.workflow.WorkflowConfigParser The config file to read. sections : list of str, optional The sections to retrieve the prior from. If ``None`` (the default), will look in sections starting with 'prior'. Returns ------- distributions.JointDistribution The prior distribution. """

    # Read variable and static parameters from the config file
    variable_params, _ = distributions.read_params_from_config(
        cp, prior_section=prior_section, vargs_section='variable_params',
        sargs_section='static_params')
    # Read constraints to apply to priors from the config file
    constraints = distributions.read_constraints_from_config(cp)
    # Get PyCBC distribution instances for each variable parameter in the
    # config file
    dists = distributions.read_distributions_from_config(cp, prior_section)
    # construct class that will return draws from the prior
    return distributions.JointDistribution(variable_params, *dists,
                                           **{"constraints": constraints})