String Sequence and Numeric Weight of Insulin.py

# python3.6
# coding: utf-8

# store the human preproinsulin sequence in a variable called preproinsulin:
preproInsulin = "malwmrllpllallalwgpdpaaafvnqhlcgshlvealylvcgergffytpktr" \
"reaedlqvgqvelgggpgagslqplalegslqkrgiveqcctsicslyqlenycn"

# store the remaining sequence elements of human insulin in variables:
lsInsulin = "malwmrllpllallalwgpdpaaa"
bInsulin = "fvnqhlcgshlvealylvcgergffytpkt"
aInsulin = "giveqcctsicslyqlenycn"
cInsulin = "rreaedlqvgqvelgggpgagslqplalegslqkr"

# Printing "the sequence of human insulin" to console using successive print() commands
print("The sequence of human preproinsulin: ")
print(preproInsulin)

# Printing to console using concatenated strings
bInsulinPrint = "The sequence of chain b of human insulin: " + bInsulin
print(bInsulinPrint)

# Printing using concatenated strings inside the print function (one-liner)
print("The sequence of chain a of human insulin: " + aInsulin)

# Concatenating chain b to chain a to make the human insulin peptide
insulin = bInsulin + aInsulin
print("The sequence of human insulin: " + insulin)

# Calculating the molecular weight of insulin
# Creating a list of the amino acid (AA) weights
aaWeights = {'A': 89.09, 'C': 121.16, 'D': 133.10, 'E': 147.13, 'F': 165.19, 'G': 75.07, 
        'H': 155.16, 'I': 131.17, 'K': 146.19, 'L': 131.17, 'M': 149.21, 'N': 132.12,
        'P': 115.13, 'Q': 146.15, 'R': 174.20, 'S': 105.09, 'T': 119.12, 'V': 117.15,
        'W': 204.23, 'Y': 181.19}
        
# Count the number of each amino acids
aaCountInsulin = ({x: float(insulin.upper().count(x)) for x in ['A', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'V', 'W', 'Y']})

# Multiply the count by the weights
molecularWeightInsulin = sum({x: (aaCountInsulin[x]*aaWeights[x]) for x in ['A', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'V', 'W', 'Y']}.values())

print("The rough molecular weight of insulin: " + str(molecularWeightInsulin))

# Calculating the percent error
molecularWeightInsulinActual = 5807.63
print("Percent error: " + str(((molecularWeightInsulin - molecularWeightInsulinActual)/molecularWeightInsulinActual)*100))