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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 geometry(AA):
    '''Generates the geometry of the requested amino acid.
    The amino acid needs to be specified by its single-letter
    code. If an invalid code is specified, the function
    returns the geometry of Glycine.'''
    if(AA=='G'):
        return GlyGeo()
    elif(AA=='A'):
        return AlaGeo()
    elif(AA=='S'):
        return SerGeo()
    elif(AA=='C'):
        return CysGeo()
    elif(AA=='V'):
        return ValGeo()
    elif(AA=='I'):
        return IleGeo()
    elif(AA=='L'):
        return LeuGeo()
    elif(AA=='T'):
        return ThrGeo()
    elif(AA=='R'):
        return ArgGeo()
    elif(AA=='K'):
        return LysGeo()
    elif(AA=='D'):
        return AspGeo()
    elif(AA=='E'):
        return GluGeo()
    elif(AA=='N'):
        return AsnGeo()
    elif(AA=='Q'):
        return GlnGeo()
    elif(AA=='M'):
        return MetGeo()
    elif(AA=='H'):
        return HisGeo()
    elif(AA=='P'):
        return ProGeo()
    elif(AA=='F'):
        return PheGeo()
    elif(AA=='Y'):
        return TyrGeo()
    elif(AA=='W'):
        return TrpGeo()
    else:
        return GlyGeo()