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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 build_srcdict(gta, prop):
 """Build a dictionary that maps from source name to the value of a source property Parameters gta : `fermipy.GTAnalysis` The analysis object prop : str The name of the property we are mapping Returns ------- odict : dict Dictionary that maps from source name to the value of the specified property """

    o = {}
    for s in gta.roi.sources:
        o[s.name] = s[prop]
    return o